It sounds like you're saving the project file. What you want to be doing is exporting a copy of the finished video. Use the "save movie file" option (in wmm 2.0) - then choose "my computer" and then the folder you'll be using to story your videos, then click "other settings" and scroll down to see all options availble to you - try the "high quality video large" option if you like wmv.
The point is you'll have to save the video to your computer first. Then you upload that video to whatever site you plan to host the vid. You can save copies of your vid that might be small enough to send by email, but it's not recommended. And you still would be saving to your computer - not with that "email" option wmm has. Most of those options aren't worth even playing with.