4.0 just came out though. My Samsung Galaxy S still uses 2.2 and apps work just fine on it.
I directed it to GB. When I load GB up it asks me to load a ROM. So I load up the .zip from my ROMs folder, and it barely loads up. All it loads is the controller part, and a black screen. Then it just crashes.
2.3 is gingerbread, and in case you didn't notice, (which you probably didn't,)