Assuming your using the WA2 as a backup, then i will continue to try and help you out.

Try using different settings. I used to have a similar problem to a game i had backed up to my computer a while back, i couldnt get the text from overlaping, and etc, and i used to have mess ups on a game that i coldnt get past the black screen, before the sony logo.

But for the error of the black screen, i had re-backed up my game into a ISO using different settings, but then agian it froze agian, after going through about 3/4 of the way.

One issue could be that WA2 is a game that is not 100% compatible with the emulator u are using. Try using ePSX or something like that, it worked fine for me for a numerous ammount of backed up games.

but some suggestions:
FPS Limit: On
FPS limit: 50-60 for a smooth gameplay and not a accelerated game play.