Help with movies

I'm trying to record some of my footage (specially the cal one), since future updates might end ruining my demos and I'll end up losing my few good frags D:
However, I have tried using holy's pack, payed attention to everything, but just can't get good video quality =(. As soon as I use the "render as.." option in Vegas, the video turns really awful compared with the original avi.
Any help out there pleaseee?

Sorry I don't use Vegas so i can't offer much help

Anyone else?

well, what's your way then?
I could make all the tga's a single avi, at a resolution of 1280x1024, and when I see it, it isn't very smooth ( I was told it is common).However, while I see it, or when I stop it, It's like if I was playing. It all looks so beautiful =D, then I use the render as... feature, and all turns ugly xD.