Only change it when it complains that it needs windows 7, i think one of the mortal kombat games did that for me.

I said it in another topic but I'll say it here too: use 64-bit win7. Newer games(say within the past 5 years from my experience) don't and won't work. They'll install but at least on mac don't open, give no error message or anything. Which honestly seems to be my experience with photon(steam play) as well when I was trying to run stuff in a vm on the mac so I guess this is a common thing(bar the fact you can actually browse the store in photon....but that doesn't solve the fact of gog galaxy not being on there, and the snap that is there doesn't really work too well in my experience...at least for games working from what i saw).

(I think I'm just cursed with bad luck when it comes to wine and getting games to work that I want to play, beyond older games that are known to work anyways)