Unfortunately, you get what you pay for. Yes, there are free programs, but I doubt they will be much better than Movie Maker. Take a look here:
Keep in mind that some of these are just trials.
If editing is something you're going to spend large amounts of time doing, it worth it to buy an editor. I use Ulead Videostudio 10+.
windows movie maker sucks is there any other freeware movie maker's out there