Problem with external Hard Drive

I sure would appreciate any help ............... I sure hope I haven't lost all my pictures etc.... (I have about 75% backed up to DVDs but ......... so much I hadn't gotten to)

Anyways ........

I have an external Maxtor Hard Drive. I forget the particulars right now, but it's large capacity, and has a one button back up feature, but I never used that.

I have it connected via a firewire, and have a DVD writer piggybacked with it.

All of a sudden, when I try to look at a file on it, or save a picture to it, I get a message that the Drive is not Formated. If I try to just view the content by dbl clicking on the drive..... I get the same message.

It's only about 6 months old ..... Any ideas on something I could try? I've ran scan disk on my main drive, turned the PC off and on, tried just restarting ... even tried system restore to a earlier date, but then I get a message saying any changes made to that drive cannot be undone.

13 year old son was using my PC to make a backup of one of his music CDs ............. I don't really think he could have done anything to cause this, but never know.