ePSXE 2.0.5 Cheat codes don't work with ISO but they do with disc

Hi all, I am new to all this.

I have been playing Spyro year of the dragon. I have a few issues. The first is even though I have followed instructions I cannot for the life of me seem to be able to create a working ISO from my disc, So I downloaded one. ePSXE sees them as the same game and loads the same set of cheat codes. The problem I am having is when I run directly from disc, the whole thing is laggy and really annoying to play, but the cheat codes all seem to work. When playing a downloaded ISO, the game runs fine but none of the cheat codes work at all. What is causing this and how can I fix it? Thanks!