How far away are you likely to be shooting? I cant recall the length of zoom on that but if you're more than 10 feet away from the stage you can turn the flash off for a start.
You'll need to have it set to a fairly high iso and large aperture (largest the camera offers really, probably f4 or 5.6 at full zoom. That should help let enough light in to keep the shots sharp. I wouldn't expect great results though. Compacts aren't designed for this type of work really.
If you have anymore questions ask away......