Your a tool!
TRY
www.ulead.com
Loads of different Programs available for 30 day trails! Check out DVD Movie Factory its very easy to use!
www.pegasys-inc.com
TMPGEnc Plus 2.5 is a little more advanced than most others, but it has a lot of options and is very fast at converting larger files, like complete movies and such. I have to say that its only downside, is its sometimes alittle picky about which files it can and cant convert! You can download a 30 day trial!
www.intervideo.com
InterVideo's WinDVD Creator 1 & 2, both solid products, very easy to use and offers great encoding quality and time.
The overall best video converter i have ever used is Ulead DVD MovieFactory SE which is the 1st program in that series. It will convert absolutely anything that you throw at it. I got it free with a digital camera i brought a couple of years back, so if you can find it i would use it!
Some AVI's & WMV's can be difficult to convert depending on the Bitrate & Audio encoding, But theres always a way.
You might have to Re-sync the Audio with the Video, you will know if you need to because it will be out-of-sync after you have recoded it, if you need to do this PM ME and i will take you through the steps. Defragmenting your HD will reduce the chance of this happening!
Heres some links to a few Tuturials, hope this help you out!
www.videohelp.com
www.doom9.org
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Make sure that all your DIVX codecs are upto date!