If you want to play Amiga500 games use "Fellow". The old MS-Dos version was quite fast even on old machines like a P233.
If you want to use the OS you could try out Amithlon but I doubt your gfx card is supported correctly.
AmigaXL sucks, it's just UAE on top of QNX.
You could also try to fine tune WinUAE to run OS friendly apps, but don't expect it to be very fast. Use separated configurations for games and OS friendly stuff.
