I downloaded a Disney DVD file (Video_TS) and used VobBlanker to change the audio from PAL to NTSC and then used FIXVTS (because of flickering of the picture). After all this I am getting a picture that flickers still. Is there something unique with Disney DVD's that you have to include another step?
Im pretty sure that when you convert between PAL and NTSC that they are recorded in different speeds (f.p.s, frames per second) this could be the cause of your problem. I say "could be" because I am not sure. but its a good place to start. Also if the movie was captured from a VHS movie that could have caused it. Bad VCR, bad recording software, bad VHS film, etc.
Well if you can get the movie on DVD you can rip it and burn it yourself and this should take care of your problem. As far as the VCR related problems I dont think those can be helped.