You may want to check out VideoSpin. It's a free program.
"Avid Technology Inc. today unveiled VideoSpin® 2.0 – an ideal solution for consumers with no video editing experience who want to quickly and effortlessly share their entertaining videos on the Web.
Support for QuickTime file import – now digital still camera and video camera owners can easily import QuickTime files and create compelling movies and slideshows"
To help with the troubleshooting, can you be more explicit and provide these details:
1.) Which camera was used?
2.) What format and resolution were the files, that it produced?
3.) How did you get these files onto your computer?
4.) What is the Project Preset (or Sequence Preset in CS4)?
5.) What is the intended delivery method and format?
As a guess from your post, I'd have said try without the MP3's, but you've already done that. It shows that something is wrong with your Assets, hence my questions above.