With some work its doable.
First if you're using bootcamp, this will create two partitions out of your physical drive, one for OSX and one for windows (the repartitioning action is non-destructive to the osx partition).
Out of the box, windows cannot read HFS+ (the disk format from Apple), but there's an application called
MacDrive which will give you the ability to access documents on the Macintosh partition
OSX can read and write the FAT32 format but you cannot create a windows partition greater then 32gig and install XP on it. XP requires partitions > 32gig to be NTFS. OSX can read but not write to NTFS. I believe there's some utilities to give write access but I'm unfamiliar with those
If you go the VM route say parallels or VMware's Fusion then you can easily set up share folders and move documents back and forth fairly easily.
Hopes this Helps