The order doesn't matter, the boot.ini file can be changed at any time to set which os boots up first by default. My computer at home dual boots Mandrake Linux and WinXP-SP2 using the Linux boot loader.

Another requirement for dual boot is the each OS has to reside on it's own partition or drive so it is a little trickier to set up on an existing HD with all of the space formatted already into 1 drive.

Cheers!
Bill