Recovery from inaccesible drive.

I have 2 partitions. I formatted one of them to load a new OS. The other partition contained Win2000Pro. and all my valuable email data etc.. The OS can’t be repaired -I’ve tried R disk etc. and the drive can’t be seen from partition one using NTFS or FAT.
Partition commander sees the drive format as “other-unix etc.” HOW can I recover my lost files?