This Rayman game in the Rayman series will always be my absolute favourite game. I love the awesome graphics (which is very impressive from a game made in 1999, the graphics were really ahead of its time), the characters (for example, the teensies, they were lovable), the soundtrack is so memorable and nice, I love the gibberish in it, and that every level is different on its own. I love that the story is dark and deep, but simple for everyone to understand, and that while it is still dark, it manages to include some humor in it still. If you own a Sega Dreamcast, then I would definitely say buy it, since it's the definitive version of the game. But if you don't have one, or just don't have enough money to buy one, then you can buy the GOG version of the game for PC, from here, because if you do, you can download the included goodies for free, or the N64 version. Both of them are worth the money. If you are into platformers, then this is the game for you. But if you never played a platformer before, then you should definitely buy this game as your first platformer. Trust me, this game is definitely worth the money. Avoid the PS1 version though, since that version only includes half of the game.
Overall, great game.