here is actually a working fix for pokemon black and white versions.Read this guide throughout.
Playing Pokemon Black on No$GBA DS Emulator What are the common Pokemon Black and White version bugs that could affect my Pokemon game and how to fix them using action replay codes:
When playing Pokemon Black No$GBA Freezes your game or turns your game into a blue screen while you are saving ?
Playing Pokemon White on No$GBA at the end of the first battlethe game freezes?
While exploring the area, the upper No$GBA portion of the screen turns to white. This is an indication that a bug is present in your file
After a long time of playing Pokemon on No$ GBA, the screen may turn white or freeze?
In NO$GBA menu enter the following as RAW action replay code Use these Raw Action Replay codes to fix the blue screen and the freezes in Pok?mon Black & White on No$Gba 2.6a.Go to Nogba top menu : Utility -> Cheats Enter them as 'ACTION REPLAY' and RAW! start with these 2 lines:
02006F2C 00000000 02180B8C 00000000
after that the code is different for the each version of Poke B&W
for Pokemon Black Version 52006f2c fdd8f1d8 02006f2c 00000000 d2000000 00000000 52180b88 42018811 52180b8c 4770d1fc 12180b8c 000046c0 d2000000 00000000
for Pokemon White Version 52006f2c fde8f1d8 02006f2c 00000000 d2000000 00000000 52180ba8 42018811 52180bac 4770d1fc 12180bac 000046c0 d2000000 00000000
Enter the codes, Click [v] AR at the menu, and RESTART the rom by going to No$GBA menu : File -> Reset Cartridge
and voila.Pokemon b&w will work.Tested on no$gba 2.6.