Three things to try:
1) The obvious: Repair permissions, reset PRAM.
if no luck...
2) Reset NVRAM using Open Firmware: hold down command-O-F at at startup, type "reset-nvram" "reset-all".
if still no luck...
3) Try a full reset: Unplug the computer from the wall, press the power button on the front (it should flash for a second), then pull out the motherboard battery. Wait at least 15 minutes, preferably at least an hour.
Put everything back together and boot up. I know that #3 has fixed firewire problems for some people, although these were usually caused by hardware issues not a software update. Worth a try, though. Oh, and I've heard people say that waiting overnight can work if an hour doesn't, but the only time I had success with this method it only took 20 minutes or so.
One more thing: It sounds like you're having camera trouble, but if it's drive problems, your drive might need a firmware update, espeically if it's an older Oxford 911-based case.
[Edit: You might also try booting from the OS install discs and running Disk Utillity to check the drive for errors, though this is a longshot. Remember NOT to run repair permissioins when booted from the install disc, though--just the disk repair.]