Umm please explain better.
If your uploading off of a digital camera then your most likely unable to change the format. Some cameras are .mov and you need to convert it. Windows will now automatically convert a .wmv .avi .mpg into .mov.
You may be seeing the quicktime icon on all videos since quicktime is your default player. If that is the case, follow this when opening a video file.
right click> open with>choose default program
Then just scroll/browse to find Windows Media player and select that. This will make all videos play in WMP by default.