Apple Do NOT do upgrade discs per-say.All OSX discs contain the FULL install packages.
Bootcamp ( the partitioning tool) is an integral part of OSx (10.6 Snow Leopard) and found in your utilities folder.
Launch this app partition your drive ( Avoid symmetrical partitions because increase the risk of accidentally over writing OSX).
Insert your windows disc and allow your mac to boot to this disc.
Select the partition you created for windows and follow the windows install (if you have allocated over 32GB for windows allow windows to reformat your partition (but not the whole disc !) to NTFS
Go through the various boot and reboot processes and about 40 minutes later you will arrive at a new Windows desktop.
At this point remove the Windows install disc in explorer and replace with your OSx (10.6) disc now run the disc and you will find that the bootcamp.exe programme will launch. Allow this to install the drivers for your Mac and reboot.
In addition to drivers bootcamp adds a Windows Control Panel that allows you to switch back to OSx.
Now spend an evening within Windows updating and installing all the security patches.
Then you are ready to install you own software, and things like Flash, Acrobat Reader,Silverlight etc...
Oh and also visit Apple top get the latest Bootcamp update from within windows.