hi am downloading an english sound vhs rip at 29.97fps and want to use that track on a all german dvdrip at 25fps that i am also downloading
(of course dont know yet if the movie starts at the exact same time ..possibly different company logos be for the actual movie and that crap,
but thats for later concern)
what is the best approach to accomplish that?
and what to use
something tells me virtualdub alone wont cut it

thanks in advance

Well, the sound would not have been recorded to match 29.97fps.
In theatre ALL movies run at 23.976fps
So it's highlikely the sound matches a 23.976fps movie.

Only solution I know is to alter the frame rate in virtualdub to 23.976 and then match the audio.

I can help you out with this if you want to.

it worked for about 20 minutes into the vid
demuxed the sound from the english VHS and added it to the german DVD
at skew -4800ms and reducing framerate to 23.976 it looked sync
but then the vhs audio got a hick up and sound was desync again
not sure if i will continue...means now i have to make at least 2 cuts to fix the sync on both parts and later merge again...hmmm will that work?

That's how I did it in the past.
Make a timeline and check where it goes out of sync. Write down the time, go to a WAV/MP3 editor (Cooledit Pro for instance) and add or delete the amount of ms you need.