I'm not a gamer so I really can't recommend a distribution other than Ubuntu for gaming.
Installing Steam I'd think would give you a variety for games.
I use to run Xubuntu and liked it-
Since you like Xubuntu you many also like Voyager. Voyager is a really nice distro if you want to stay with a Ubuntu based system.
As far as which distribution it really depends on what your going to use it for.
Is this primarily for home use?
Here's an article for game emulators:
I've never heard of one that actually worked with Linux under Wine.
I recommend Debian because it is rock solid. Once you get to know the package management system Debian is fairly easy to run. Reading the documentation will help.