I'd like to install both Ubuntu 12.04 and Windows XP on a Dell laptop, and I was thinking about using a dual boot structure, and using the bulk of my hard drive as empty hard drive space to share files between the two operating systems (so choice of file system type is very important in this set-up).

The kind of partitioning structure I would like to use is

Partition 1 - Ubuntu 12.04 (root) (20GB)

Partition 2 - Ubuntu /home (20GB)

Partition 3 : Free Space (560GB)

Partition 4 : Windows XP (35GB)

Partition 5 : SWAP (3GB)

(Total Hardrive Capacity is ~640GB)

My question is; what is the best way to go about setting up this kind this system?

Should I install Windows XP first and setup the partitions, and then install Ubuntu which I believe will install the GRUB bootloader for OS booting choice

or

Do I install Ubuntu first, setting up the available partitions and then perform a WIndows install?

Please let me know if there is anything in this setup that I have left out and should know about, including things related to setting particular partitions as logical or primary, and whether the boot partition and the filesystem partition should actually be two separate partitions.