I render as .wmv through Vegas using pretty much the default settings. A 4 minute edited video would come out at around 50mb. I then upload straight to youtube and get full 720p options once the video has been processed. It's also a great size and quality to host elsewhere if people want it on their hard drive.
Windows Movie Maker allows you to save as .wmv so if you have raw HD fraps footage you want to upload to Youtube, put it through Windows Movie Maker and save as .wmv. Depending on the length of your raw footage you'll get a fantastic quality to size ratio.