Virtualdub - vista Codec problems

Have gradually been loading my new Dimension 9200 running Vista with the applications that I wish to use. I used Virtualdub a lot on my previous xp machine and have successfully loaded current version onto my new machine running vista. Program works ok but has some limitations that I am keen to overcome:

a) I used to compress virtualdub files using Microsoft MPEG4 Video codec v1 on my xp machine but very few codecs actually appear for use currently on my vista machine with no MPEG4 V1, V2 or V3 that I previously had. Do I need to download some more codecs and, if I do, where can I obtain them from for Vista.

b) AVI files open ok in virtualdub on vista machine but I cannot open files that I processed and saved using virtualdub on my old xp machine (Using MPEG4 v1 codec referred to in a) above. Virtualdub shows following message:

"Couldnt locate decompressor for format MPEG4 (Microsoft High-Speed MPEG-4).

Virtuadub requires a Video for Windows (VFW) compatible codec to decompress video. DirectShow codecs such as those used by Windows Media Player are not suitable."

The file does play on Media Player V11 that came with Vista machine.

Please can someone advise me on how i go about getting and installing apprepriate codec to resolve this virtualdub problem in vista.

 

Many thanks Haffy