Last night, I burned a LiveCD of Ubuntu to try and boot on my IceBook G3. I popped it in the drive, rebooted holding "C". Well, for some reason it didn't work and booted to Tiger instead. So I tried again, and this time it booted to a blank grey screen. Restarted, did same thing. Now, I took the disk out and tried to boot into Tiger as usual. Same thing happened, and every time I try, it still "boots" to that grey screen. Is my Tiger install botched? What can I do to restore it?