The most distinctive graphical feature of the Amiga library must be the smoothly gradiated backgrounds. Through the exploitation of a hardware quirk programmers could exceed the usual colour limits of the system.
WinUAE is the emulator of choice, but setting it up may require assistance—for Amiga novices, anyway. Look for pre-configured versions.
Most games released in the late 80s and early 90s run fine on an Amiga 500. For everything newer it's best to change the config to an Amiga 1200 (or 4000, they're basically the same) and make use of its higher clock speed, increased RAM and AGA chipset (more colorful graphics). After the mid 90s more games were AGA only and therefore don't run on a 500 at all, but if you're downloading good ROMsets, they should be labeled as such. The latest 3D games also needed a turbo card, but I don't know if they're emulated yet. They also don't come on disks, but CDs and can be installed to HDD.
So yeah, there are basically three types of games and emulator setups to worry about. OCS/ECS games, AGA games, and turbo card accelerated games. The first two probably make up 90% of the entire library, and backwards compatibility is usually fine, so I'd say you'll be able to play almost everything worth playing on an Amiga 1200 config and matching kickstart ROM (v2.x or v3.x).
Last updated: September 10th, 2011