There are many editions of C&S, and their approaches are somewhat different. This Wikipedia article actually does a pretty good job of describing those differences; an additional article about an unauthorized version adds some more fuel to the fire. Full disclosure: around 1999-2000, I was in talks with the current copyright holder of Arden to republish the book. It appears there may have been some legal issues in doing that, but at the time I wasn't aware of any. Anyway, I pretty much removed myself from the C&S community (or whatever you want to call it) a number of years ago due to what I felt was a complete disregard for the original vision of the game and a lack of progress on the part of the trademark owners. Apparently from some posts I read on the fan forum (LOCS is LONG dead unfortunately) Mystic Station is working on a new 5th edition to be released sometime this year. Best of luck, but if they wanted to do the fans a service they'd simply re-release a nicely cleaned up 1st edition. Okay, enough complaining...
C&S 1st and 2nd editions are close enough to lump together for this post. Major differences are the addition of TES (thievish experience skills), moving some stuff like mass combat to the sourcebook, CRs for attributes and better organization. At least you can actually read the text in the 2nd edition; 1st is microprint. It literally looks like a 2 point font. Regardless, the 1st edition Red Book is probably the best value for your gaming dollar, if you can find a copy. I never actually played 1st edition, as my first experience with the game was purchasing a copy of the 2nd edition boxed set when I was around 15. I did get my hands on 1st edition soon thereafter, and mined it for endless ideas. I had a 2nd edition campaign for a while, which was really more like "make characters using C&S but we'll use Rolemaster for combat and D&D for all the magic items". At the time that didn't seem odd at all, but now I wonder how I figured out what the hell I was doing. Played 3rd edition once, 4th a few times. Unmemorable. 3rd was essentially an attempt to create a unified mechanic for C&S (which is stupid if you ask me, especially for a game that prides itself on complexity) and dumb down the character creation process. Consequently, all the flavor got sucked out and the game was left a boring, uninspired mess. I'm sure there's a good rpg floating around somewhere in those rules, but it's not C&S. 4th edition was called Rebirth and tried to rectify the downward spiral the game was taking. It was a valiant effort, but modern sensibilities don't work with a crusty old horse like C&S and thus the game was a failure. At least to me. I tried to like it, but like strawberry ice cream, it felt as if I was forcing myself to eat it simply because it was available. Give me chocolate or vanilla, fruit is for women. What all this means is, basically, you have one real version of the game and a couple versions that came out after that don't resemble the original enough to share the same name. When I talk about C&S, I specifically mean 1st/2nd edition, along with all the supplements and sourcebooks. 3rd might as well not exist, 4th has some good ideas but nothing worth worrying about except the Armourer's Companion, which is pretty good.
In light of that, how does C&S actually play? First, character creation. Making a character is half the fun, and to the uninitiated, an all-day affair. If you've never played C&S before don't even bother with a wizard; you'll just get frustrated and start throwing shit. Here's a character sheet:
All that stuff has to be calculated. PCF and PMF are two of the most important pieces of information for a character. Figuring out these values takes some time and a calculator. If you don't have a calculator, it will take quite a bit more time unless you have Rainman-level mathematical skills. Nothing complicated, but there's a lot of math involved. Prorating a character means you get experience points and level him up. C&S doesn't assume anyone is a 1st level rube, but instead ties ability to age. Unless you wanted to spend 90% of the campaign enchanting items behind the scenes, hope your wizard was Good Aspected and over 30 when play began. Old wizards actually got to cast spells and have cool stuff; young ones spent most of the time looking for dragon skin and rare woods to make crap. If you got lucky (or cheated), and rolled up a blue blood knight (or prince), it was possible to start with enough money and influence to have a small keep or even a castle. Constructing your dominion might take a while, but worth it. Buying equipment and supplies was akin to going to a market as the variety was staggering. Trying to figure out how much food was needed for an expedition was not something to be taken lightly. If you're curious, buying whole wheat bread, poor cheese and plums was the cheapest way to keep nourished. No guarantees on the quality of future meals.
Yes, yes, you know all this crap. You've read the reviews and articles, you want to know how the game PLAYS, once you've gotten the character in hand, ready to go. To be perfectly honest, it's just an overtly complex version of D&D. Combat is pretty much the same (roll a d20), although armor is broken down into its component parts. Fighter-types are nearly supreme in martial affairs, and you do not want to fuck with a knight of great renown. Still, it's D&D with a bunch of cool tactical additions and A LOT of atmosphere. Probably by design, wizards were not fireball throwing gunslingers like those in D&D. I played an Enchanter who never cast one spell over the course of 5 or 6 sessions; in-game it made sense. Considering how hard it was to create that character in the first place, how difficult it was to understand the processes that constituted the making of a magic lute, the amount of real time it took figure out how long wood required to become BMR 0 and thus enchantable...that character wasn't about to waste 6 months of work on some ruffians in a back alley. Dealing with bandits was for knights and yeomen, not a scholar. Similarly, I ran a goblin thief for a while and don't think he ever got into a scrap. The one knight I had, cousin to the Crown Prince, regularly waded into battle to make a name for himself. He also killed a few commoners who tried to steal his horse. Would this happen in D&D? Possibly, but maybe not.
C&S is not a game to be taken lightly; in fact, to play it at all requires much more attention than a game such as D&D. RuneQuest had the idea that limbs could be hacked off and hit points weren't unified; at least you could be magically healed. C&S took this a step further and had rules for chirurgeons with the ability to set bones and perform surgeries. When coupled with the insanely detailed rules for building construction and magical research, most of the game was spent in "down time", with a focus on what the characters were doing when NOT adventuring. It was far more fun to make up characters and age them, never once doing any sort of dungeon delving. The system itself was designed for all the offscreen activities, and that has always been the appeal of C&S to me. Consequently, it is why 3rd and 4th edition failed as they attempted to allow for easier adventuring. The proper feel of C&S, when adventuring, is akin to reading Le Morte or Lord of the Rings: utter dread and near futility. The purpose isn't for fun, it's to accomplish a goal, unlike D&D which implies adventuring is valuable in itself. I enjoy both gaming styles, but the distinction must be understood to fully realize the intent of C&S, why all the real action goes on when the DM isn't running a session but instead getting emails from the players about a new barricade constructed to keep out highwaymen or a list of items intended for enchantment. Adventuring in C&S is a way to make money to do all these things.