Burning Speeds and Iso's

I wondering what will be the best speed for me to burn saturn games iso on and do have to change the region on a european saturn ISO to make it work on a US saturn.

AS far as I know, you can burn anything as fast as you want. You only want to slow down when you are using cheap discs that are showing errors.

Can't answer the reigion question, but my guess is it would be harder than its worth, and you usually can't magically make one region turn into another.