Windows video editor wont work why?

i hav a lumix camera and it wont open the videos with windows video editor what format do i need the videos in to get them to work and where could i find a converter to do that ???quick answer would be great :) You may try this AVS Video Editor which has many great functions. The features in the official site are below:1. Direct Transfer to iPod, PSP, Mobiles and Other Portable Players2. Supports Virtually ALL Video Formats3. Burn Movie DVDs4. Capture and Edit Video from External Devices5. Edit Video and Enhance Your Movies6. Create Slide Shows7. Make Perfect Audio for Your Video Editing Tasks8. Scene Detection9. Convenient Video Editing Tools and Interface