So far your work has been great. But, I wanted to let you know that I am having a lot of problems viewing it on xtube. You may want to consider posting it elsewhere too.
I use Windows Movie Maker. It's an optional program that comes with XP Pro. There are several other apps that work similarly.
Basically, you import all the movie clips you want to use. You can split them, move them, etc. until you have them where you want them. Usually you can also insert still photos (JPGs) as well.
Then you can add an audio track that will play in conjunction with the videos, or you can turn the video volume off.
Then you can usually add a text overlay "track" for whatever captions you want.
Save the whole thing as a .avi or .wmv, and you're in business.
I use make all of my compositions with Adobe premiere CS3. Is a very complete tool with a lot of pluggins to make great compositions. If you want somethig easier to use, windows movie maker is a good choice.