Get multi-language panic message after every reboot

As the title says, every time I reboot I get the multi-language kernel panic message (You need to restart your computer. Please hold down the power button for....).

I've managed to get into the GUI by using different combinations of keys. I can't remember what they are (it's been different every time), but I believe one time it was holding 'x'. This time, I held Command+V to run what looked like a diagnostic POST (I actually did this to see where in the bootup it hanged, but instead it booted to GUI).

Any idea what this could be? I don't think anyone has added any third-party RAM (this was not my machine originally, I took over a position for another person), is there a way I can check if any RAM has been added?

I'm running 10.5.8 with 2GB 667 MHz DDR2 and a 2x2.66 Dual Core Intel Xeon.

Here's the Problem Report for Mac OS X Kernel:

Any help is appreciated!
*Note* I also have trouble with Safari sometimes when opening up a second tab it crashes. I cleared my preferences (.plists, etc.) and it still happened, but it didn't happen upon this reboot. I don't know if that may have something to do with it.

Software on machine is Adobe CS3 and MS Office 2k8

 

That seems to have fixed the problem with rebooting. What gave away that it was a problem with Parallels, and what was the problem?

Now, I have the problem with Safari, except now rather than not able to open a 2nd tab, it crashes upon loading period. Here's the problem report for Safari:

 

Just had another kernel panic while my Mac was idle with just Firefox open. Here's the problem report: