Need Emergency help

First off let me explain why I'm so desperate for help, if you don't care, skip to the next paragraph for my computer issues. Just yesterday, my grandmother passed away. We have searched for her last will and testament, however we can't seem to find the printed version. So tonight, as I turn on to her computer for the saved document, the computer starts having severe issues [will describe in next paragraph]. I need to find the files on this computer, for my families sake. Please if anyone is out there who can help, I will take any advice on either returning the computer to working order, or getting as many files off the computer as possible.

Type of computer: Dell, Inspiron 530 written at the top, OS: Vista. Today when the computer was turned on, everything seemed to be in working order, until I tried to open a file. At that point all icon's disappeared, and all i can see is the background image. Ctrl-Alt-Delete isn't working. Attempting to restart the computer has given me the same issue, except the icons never appear. From what I have read on other forums, I need to run the computer in safe mode.

I am incredibly wary of trying anything with so much on the line. Is there anything I can try, that will definitely not run the risk of further messing up the computer? And how do I turn off the computer, making sure not to further compromise the system? Should I just go directly to a professional?

Thanks for all of your future input, everyone. My family and I truly appreciate it...