i haven't been here in a while and i'm not sure if this is the right place to ask but... i recently had the firmware 3.52 M33-2 (the custom one), and everything ran great and smoothly iso-wise... then today i went ahead and updated to 4.01 m33-2 (newest custom firmware) with the 1.50 kernal add-on..
now most of my iso's work except a certain one, its "Dragonball Z: Shin Budokai"... the game starts then it goes though all the logo's screen (brands and what not), then it just freezes after the last one and restarts itself. before when i had 3.52 M33 it ran just smoothly.. anyone know what the problem might be???
You could also try deleting the game save for that game. There could be a possibility it is getting hung at the game save if it is trying to load it. There have been some that have had issues with game saves being compatible between 3.52 M33 and firmware above it.
If it's a rip, and not the full game, it could possibly have compatibility issues. If it's cut down rip, try looking for a full one.
A ripped copy of Daxter used to work fine when I was on 3.52 m33... then when i upgraded to 3.72 or 3.90 m33, it would freeze, not load... all sorts of things. Downloaded the full game, no problems.
edit: you could also try different UMD emulation methods.