Partition Table Problem with Hard Drive

I have two hard drives in my system and am running Windows XP
Professional. I have two problems with this.

First, my computer randomly reboots every day or so. After looking at
the system part of the event viewer around the time these reboots
occur I have a error msg saying:
The Device \Harddisk2\D is not ready for access yet.
I'm not sure if this is what's causing the reboot or if it's just
after the reboot and if this is a problem or not.

Second, I use Partition Magic 8.0 and for some reason it won't run.
When I try to open it it says:
Init Failed: Error 100
Partition Table is bad
How do I correct this problem? Is my hard drive possibly bad and is
there a program such as Norton Utilities (which I have) that I can run
to fix this? Or do I have to make a backup, reformat my hard drive,
and reinstall this?

Third, are these two problems connected?

Thanks.