^^ what he/she said.
Get the system you like the games for, so right now the biggest games are:
xbox: Halo(2), Knights of old republic, Ninja Gaiden. I would avoid the xbox if i was a rpg fan at all costs (unless Fable ever comes out). You have to pay $50/yr to get online via xbox Live in addition to your already broadband fees. Good thing about the xbox is that its very hackable (see xbox-scene.com) and comes built in with a 8gb hd (no need for memory cards ala Ps2 for now), ethernet connection, and four controller ports. Unlike the PS2 which only has 2 controller ports.
PS2: None of the above games but pretty much everything else. Note that some of the pc to PS2 game conversions suck on the PS2 (Max Payne) and are better on the xbox. Most online games are free besides Final Fantasy and Everquest. Ofcourse you have to pay for broadband, but no additional fees like xbox. You do have to buy the network adapter, which is a one time fee.
Gamecube: Mario, Zelda, Metroid, Resident Evil 4. I am not sure if EA is still making sports games for it or was it Sega that dropped support? Also, Gamecube has little to no online games, although it supports broadband connection. Square/Enix are starting to make rpg's for it, albeit a little slow they are at doing that.
ALL of the systems come with one controller and system only. Unless you buy one of the various bundle deals...