Trying to get fat32 hard drive to work on XP

I recently purchased a WD My Passport 1TB portable hard drive and a friend of mine formatted it to FAT32 on his mac so I can use it on both my windows laptop & his mac. He then continued to save files I wanted off his laptop. I have a laptop that uses windows XP though & have discovered that it registers that the hard drive is plugged in but I cannot open it, and that it wants to format the drive again...

Is there any way I can get the drive to work without losing all of its contents?

...or will I have to re-format the drive again & loose everything??

Plus, if I do have to re-format, is there any recommendations of what to format it to so that I can use on both mac & windows??

Any advice will be a HUGE help!!

Cheers.