For settings, I like the D&D Forgotten Realms, DragonLance, Dark Sun settings. I also like the ShadowRun and Mechwarrior settings quite a bit. Mostly, the books(novels that is) tend to bring things alive for me which is why these are the ones I like.
D&D(the most) since the early-mid 80's starting with Red Box, AD&D, AD&D 2Ed, D&D 3.5, D&D 4E. Also played ShadowRun, Paranoid, RoleMaster/MERP, Battletech/Mechwarrior, and I am sure a few others I have forgotten. I have recently gotten interested in Savage Worlds but yet to play more than a demo game... Hoping one of our group's GM's will actually start the Super's campaign we have talked about recently in the near future. Way back, I was very intrigued by the whole RoleMaster/MERP system and its detail, but at the same time that's what drove me from it was the slow nature of all of the lookup tables. These days, I would be much more open to using that type of system as I would use my VTT(MapTool) to program all of the look ups and record keeping for me(though that in itself would be a massive undertaking!) I use my computer for rolling instead of real dice almost exclusively for the speed it brings both as a player and GM.