Is virtualdub the best way to get video and audio ligned back up?

After DL a 2 CD AVI movie, I combined them using virtualdub. It combined great. I used DVD Santa to convert the big AVI and burn. But the end was that the audio was about a half second behind the video on some scenes. But not all.

I suspect that the clipped video for compression/conversion was what caused the audio to be off in some scenes.

I used virtualdub to increase and decrease some scenes but the entire movie would have to be done.

The 2 AVI files, before the combine with virtualdub, are just fine. So is virtualdub the only way to fix this? Or is there a better way to combine to not lose the alignment like settings I am over looking in virtualdub?

Thanks
Mustang