I don't think updating BIOS is anything a noob shoulod be trying. It's one thing to not be able to boot an OS and quite another not being able to...
You could try some kernel boot otions like nohz=off or acpi=off (or both). You could also try the Ubuntu forums.
Well if was me I would download and burn a live DVD and check it out myself. Most modern hardware is supported by linux these days.
Well it depends... Did you have linux on it before it stopped booting? If it's a Windows only PC then no linux won't help. Use your Windows DVD.
You could do something like this:
Step1 - ls /path/to/source/ > exclude.txt
Step2 - rsync -av --delete --exclude-from=exclude.txt /path/to/source/...
Separate names with a comma.