I forgot to have a look last night but will try to do it tonight - I only have Virtual Dub installed at home, not at work.
Video on computers is a complicated field though. When you 'save' video you have a huge range of options, such as:
- What "frame size" to use, i.e. 640 x 480 or 320 x 240;
- What level of "compression" to use - the more you compress it the smaller the file but the worse the quality;
- What "container" to use, i.e AVI, MPEG, MOV etc.;
- What "codec" to use, i.e. what method of compression.
It's a confusing business. I am guessing that your original file is highly compressed but when you saved it you chose less compression, which could explain why the file ended up bigger.
Are you trying to make the file smaller (i.e. have the same running length but take up less disk space) or are you trying to make the movie itself shorter (i.e. cut bits out)?
Nelviticus