I think Suse is good for newbies. As easy as XP, probably, esp if you were just putting it on a clean machine. The hard bit always tends to be when you want the PC to share windows and linux - and you don't want to screww anything up
ATI can be a hassle, tho should be okay. Should get 2D on install and will need a binary driver for 3D. The nforce2 chipset needs the latest versions of linux, like mandrake 10. Don't know what version of Suse is needed.
Lots or native little games to linux. Big games are generally all the ID games plus UT multiplayer - so thats all your quakes, return to wolfenstien, Unreal Tournament all versions, etc. Other games like half-life, counterstrike, various jedi knight and many others run well with the Winex ($15) compatibility layer.
All normal tools are good with linux. Mozilla, firefox, openoffice, etc... Other thing are hard to get, but you can use crossover ($40) to run apps you need. It will run a lot of windows stuff like MS Office and Photoshop and such...