Something you can get for free is VirtualDub (
clicky). It can't handle WMV straight (with Avisynth it can, though), but I think it's the best for the final saving to XVid/something- encoded video. It's pretty rough, but you should get the hang of it.
The Windows Movie Maker is pretty good for the basic editing, but I prefer something else than WMV for saving (I save it as the "RAW"- AVI it can produce and open it in VirtualDub for final saving).
There's Jashaka then, although I haven't tried it myself. Give it a go if you want (
click) , it seems very good. As the last, there's Cinelerra (
clicky), which could be your video heaven - if you're running Linux, that is. You'll have to compile it yourself for Win32, or find someone who's making Win32 builds of it.
Those're the ones I'd recommend.