One approach to booting Linux, XP and Windows 7

So this is my configuration. I like to keep around a toy Windows OS for iTunes (for iPhone jailbreak) and games.  These are all primary partitions:

• Drive 1:
• Partition 1 (35GB): Windows XP
• Partition 2 (55GB): Windows 7 RC (shiny toy)
  
• Partition 3 (rest): Linux data (/home - the serious stuff)
• Drive 2:
• Partition 1 (30GB): Ubuntu Linux 9.04
  
• Partition 2 (15GB): (to test other distros on the hardware)
  
• Partition 3 (2GB): Linux swap
• Partition 4 (rest): Windows data (C:\User - games & media)

The things I figured out to make it work:

1. Do all partitioning before installing Windows, and only use Linux to edit partitions (cfdisk or gparted).  
• The Windows 7 partition manager confuses XP because Windows 7 changes from "cylinder aligned" to "megabyte aligned" partitions.  However, both can understand what Linux writes. 
2. For Windows XP to complete installing, you have to install it before installing Windows 7. 
   
3. Let Windows 7 have the MBR on Drive1, which gives options to boot Windows 7 or XP.  Install the GRUB MBR on Drive 2, and set the BIOS to boot Drive 2 first so that GRUB runs by default.  I figure keeping the bootloader could be handy.
• Or: use GRUB only and overwrite the Windows 7 MBR with GRUB
  
• Or: install NeoGRUB on Windows 7 and add a chainloader for the Linux partition
  
4. Putting the data on the opposite drive from its host OS is to avoid user disk operations slowing the running OS.  However, the drives are not independent - you don't have "windows drive" and a "linux drive".

Hope someone finds it useful.