I'm just getting started with Ubuntu, but love it so far.

I plan to get into some basic screen casting and editing for the purpose of tutorials. Is there any linux-compatible video editing software which you would recommend? I'd like to be able to zoom in on certain zones of the video as needed and annotate as well.

Ubuntu 8.04 Hardy Heron
Dell Inspiron 1501 Laptop, Dual Core AMD
120GB HD