Just wanted to follow up with a solution that seems to be working so far...
To stop my computer from freezing up on hibernate, I disabled most (if not all) of the power management using kernel params on boot. I edited my /boot/grub/menu.lst file to have this as the first line...
kernel (hd0,0)/boot/vmlinuz BOOT_IMAGE=linux root=/dev/sda1 noapic nolapic resume=/dev/sda6 splash=silent acpi=no apm=off vga=788
note the acpi=no, noapic, nolapic and apm=off
Next, I went into the Control Center->Peripherals->Display settings and disabled all the settings in the "Power Control" tab.
So far, I have yet to go into hibernation / sleep / suspense, and everything is working well. Keeping my fingers crossed!
If anyone sees any problems / issues with what I did, or has some helpful advice, please post!