Movie Maker and Vegas are two good programs.

Movie Maker is free, easy to use, and what I learned on. Pretty good all around.
Vegas is not a free program, but is nice to use and has a better capture than WMM (raws take up alot of space, I got a 200gig hard drive because my little 40 was being cooked by the captures in Vegas) I do not know it very well, but it is more complex than WMM and I have not been able to find out everything and make everything work.

I have example of some vids I made in each system on my website
The Windows Movie Maker examples are here:
[link=http://www.tjbatix.com/foamt.wmv]Flying foamy in tennis courts at night[/link] <== I think this is best vid I made in WMM
[link=http://www.tjbatix.com/whe.wmv]Wild Hare 28% edge batix[/link]
[link=http://www.tjbatix.com/tj-best.wmv]Best of Throttle Junkies[/link]
Here are some vids I made in Vegas:
[link=http://www.tjbatix.com/brett.wmv]Brett 3Ding[/link]
[link=http://www.tjbatix.com/stupid.wmv]Flying another foamy in tennis courts @ night, silly vid[/link]
[link=http://www.tjbatix.com/xacfinal.wmv]XAC event overview[/link]<== 1st Vegas vid I made (I think) and uses Vegas's transitions and extras more than most of my other videos.

I personally like better quality of raws from Vegas, but it seems a little clumsy and not the best layout IMO (given I have not taken much time to really get into Vegas's features so it may be a null opinion) I like WMM, has a lot to offer for a free program but a bit confined once you know it well enough.