I've come across a good few in my time so I might be able to help you out. There's one called Wax which is a free video editor but honestly its not all that good. There's Windows Movie Maker that is notoriously poor. There's a 3D animations software that I use call Blender that as an built in video editor which works quite well (however it might take a bit of tutorial work to learn out to use it).
Out of the three which I've mention that are free... I'd say Blender is the more advanced, in-depth one. However it does have a pretty steep learning curve that might be a little over kill for what your trying to do. I'd say WMM is probably the worse of them.
As for paid, erm I here After Effects is probably one of the best out there that you can get however its expensive, like really expensive specially for something like what your doing. There is another program that you sometimes get for free when you get a video camera (I did) however I forgot what its called (its on the other comp and I can't be arsed finding the CD out), got the older version too so I don't know if they do the new version of it for free with the cams.
What I can recommend doing is to just type in "Freeware video editors" and looking at what you can find and what is appropriate. Best of luck.
Threw this together real quick