Works better for me
Gauntlets works better for me, but far from perfect.
The screen flickers during the opening bit and then I step into the red "I" portal to start wacking endless bad guys. If this is where you crash, maybe you have a bad rom or somesuch thing because I get to the mountain-side with the endless irritating sword-guys. Use the 'good' tool as outlined in the faq to check your rom. If that isn't it, try updating your graphics driver or one of the other generic things in the faq.
Now, after I play for 15 minutes or so, the flickering on the 'battle' screen seems to get a bit worse - but still playable even on my wimpy GeForce 256. However, the sound gets corrupted such that the background music is random electronic blurps! Funky. Still playable - if you consider the original game to be 'playable' that is!