For low-light shooting, there's some consensus that the recent Fuji cameras (notably, the Fuji F30) have excellent performance. The only way you're going to do better is to get a D-SLR. (Larger sensors == lower noise at high ISO.)

Photo trivia: every time you double your ISO, you also double your flash range. So, regardless of the camera, cranking up the ISO will give you more flash range. Flashes are rated in their "guide number", which equals the distance (in feet) times the f-stop at ISO 100. (Guide numbers are also reported for meters, for the rest of the world...). If you want more flash range, then you either want a wider aperture, or a higher film speed.

Inevitably, the real problem is that a flash can only get one target at the correct illumination. Anything closer gets blown out and anything farther away goes dark. The "real" answer, for indoor, nighttime shooting, is to shoot without a flash at all. This is where the high ISO can be a real winner. (Or, if you want to do indoor illumination properly, you need to either bounce light off the ceiling or have multiple 'slave' strobes. It gets complicated very quickly.)