Crt resolution issues

Hey guys. Ive been running retroarch on windows 7 thru a crt tv. Sometimes, some games are out of range n i get the bad Vhold. I was wondering if theres a way to select the resolution you want before launching a game because I cant see anything once it starts flipping and am not able to change the resolution. This happens mainly in 32x and a few atari 2600 games. Any thoughts? Thanks,