Here's what I do.
1. Import all the video into Windows Movie Maker and arrange it into a nice fight video.
2. If the total length of the video is more than about 5 minutes, cut out the less-interesting parts until it's 5 minutes or less (5:30 at most).
3. When saving the movie file, check "Fit to file size..." rather than "Best quality playback for my computer". (Best quality for your computer =/= best quality for Internet.)
4. Make the target file size as small as possible while keeping 640x480 resolution. (Usually the kbps will be ~500-550.) For a 5-minute video, the file size will be a little over 20 MB.
5. ????
6. Profit.