Pokemon Soulsilver(U) help in No$gba emulator

MY game shows "rom crashed" right after i beat Morty of ecruteak city gym.Plz help

Try to play it on DeSmuMe instead.

Does it work on XP???

Yes, it is.
Just download the right one, x86 or x64.

when i try it with DeSmuMe, it has a very slow game speed, how can you fix it?

DeSmuMe depends on your computer specs,
If you have a high end of pc spec, you may get an overalls good speeds.If you can't cope with the slow speed, just switch to no$gba,
and back to desmume if you got permanent freeze point.

now its having problem at first gym.