During start-up, window appears telling me to restart... how do i fix this?

Question

i try to turn it on and this window appears telling me i need to restart my computer. i press and hold the power button until it turns off, let it sit for a minute, then turn it back on and the same message appears. i've done this multiple times and the same thing always happens. i called applecare and they said the next step was to reinstall the mac os and wipe my hard drive clean. is there something else i can try before i do that? i really don't want to lose all the stuff on my hard drive (didn't back it up).

Answer 1

You're getting what's called a kernel panic.
http://docs.info.apple.com/article.html?artnum=106227
It can be caused by either hardware or software. If you have any peripherals attached, e.g. external mouse, remove them.
You could try to boot in safe mode by holding the Shift key as you reboot:
http://docs.info.apple.com/article.html?artnum=107393
http://docs.info.apple.com/article.html?artnum=107392
A safe boot will, among other things, do a disk repair. If you can get booted up, use the opportunity to back up. You could then try to boot normally.
If that doesn't work, start up with your install disc by holding down the C key while rebooting with the disc inserted. If you then do an "archive and install", it will replace your system files without erasing your data:
http://docs.info.apple.com/article.html?artnum=107120