NeoRage (0.8c) is my favorite Neo Geo emulator.
It's compatible with Windows XP.
Nebula (2.23d) is a great emulator that
I've been using with newer games. First class!
RockNES X (2.0 beta2) is my favorite. It's
based on the DOS-based RockNES.
FCE Ultra (0.50) is an
excellent emulator with adjustable video modes and Game Genie support.
ZNES (1.36) is a great
DOS-based emulator that supports triple-buffering and various video modes.
Snes9x (1.42) is another good
emulator that supports all the popular "rendering" modes.
Project64 (1.4) is a
somewhat complex, but robust emulator for the Nintendo 64.
VisualBoyAdvance (1.5.1) plays
all Game Boy, Game Boy Color and Game Boy Advance games.
Gens (2.11) includes
lots of rendering modes to smoothen edges and plays MD, Mega-CD and 32X
Meka (0.65c) is a very
nice emulator that plays Master System as well as Mark III, Game Gear and