You'd better describe a few about you tab and how it doesn't work on youtube, so we can know how to work it out. Youtube works on Android 2.2 OS basically, and you need to install the youtube and flash app. You also can try to visit youtube on certain browsers such as skyfire.
First you need to sure your tablet support adobe flash and then see whether the tablet already has one
If not, you can download one from android market or some website
