help to access external HD from PC and Mac

I'm regularly a PC user but have just purchased a second computer
which is a MAC. I backup my data to a 500GB External HD with 5 NTFS
partitions of 100GB each. Each partition contains a different type of
date, ie Music, Videos, Docs, etc. I used separate partition to avoid
the risk of corrupting all my data if murphy visits. (This has
happened.)

With my new mac, my goal now is to be able to use this so I can have 1
common storage for both my PC and Mac. I want to be able to access the
data in the HD from both computers. NTFS doesn't work because it is
not supported natively by Mac.

I'm stumped. At first I had planned to do repartition and reformat
with FAT32 since it's accessible by both systems but since FAT32 has
size limits my 100GB partitions can't be formatted as Fat32. I can't
do NTFS because Mac can't access it. I can't do HFS because PC can't
access it. I need 1 HD accessible by both PC and Mac.

Help! Any suggestions? I really appreciate it because I'm stumped.
Thanks.