'Locking' a video within my video

Hello,

First of all, I'm new here and I just started using Sony Vegas Pro. My English isn't very good so I can't really explain what I want, so I just rendered this video to make clear what my problem is.

http://f1.creativecow.net/4859/my-problem?uploaded=file

I tried to zoom in with the Pan/Crop tool, but then, the video file that's in my video starts to move along and I just want to keep it in the position that it's originally in. So that video shouldn't move, but I don't know how to 'lock' that video and I don't know if that's even possible? If yes, I'd like to know how :)

Thanks for your time!

Just what I needed, thank you so much!