In theory, FAT32 is your best shot. It can be written to by both operating systems, problem is you're limited to 32 gigs. Since most external hard drives are larger, NTFS is the way to go. You won't get the performance of FAT32, but you will get the space.
can you tell me were you got this 32gb thing from
What is the best file system for an external drive, so I can use it in both OS X and Windows.
can you tell me were you got this 32gb thing from as i have two external drives one NTFS and one FAT32, the FAT32 one is 400gb split in two and i use the full 200gb for windows stuff.If i did'nt need
it too write from OS X id use NTFS all the time as FAT32 is old and cruddy
That 32 GB is a Windows OS limitation, I believe. MacDrive is a fantastic product, by the way.