Word of warning, don't use CampTune (an 'on the fly' repartitioner) Tried it yesterday and had to reinstall my OS X partition so great was the damage it cause.
Apologies for seemingly resurrecting an old thread but there is reference to a posting in this thread so it is better to keep everything in one place.
I did succesfully use Paragon Partition Manager 11 to resize Windows 7 / OS X Snow Leopard partition (Windows was set as default boot partition).
Other observations: When you have windows running in BootCamp (dual boot OS X and windows on the same internal HDD): It is possible to use to use the Windows 7 install DVD and delete the OS X partitions leaving only the Windows partition(s). Then reboot and once again start from the Windows DVD and do a repair. The disk is converted to a MBR partitioning scheme and will happily boot Windows.
However using subsequently Paragon Partition Manager 11 to move the partition from the "end" to the "front" of the drive (have the empty space "behind" the Windows partition failed but that may be because I got impatient since the progress bar had stopped and I suspected a hang. When I get some time I might try this again and then extend the Windows 7 partition instead, doing a defrag and then shrinking it. (If I do then I'll report back on the results.)
Windows 7 will also install happily as the only OS (wiping the HDD) and will create a MBR partitioning scheme. The only thing needed is the install DVD to install "Boot Camp" which does install all the required Mac drivers for Windows to run and installs the Apple Update program ( it will then detect if updates to Boot Camp is available plus it will give options to download Safari and iTunes/ Quicktime for windows). Windows 7 backup and restore works fine after you have made a recovery boot CD as prompted by Windows.
If you opt for only Windows (and no OS X) then Apple support is unlikely going to troubleshoot a Windows installation so you are out on your own.
After a long absence I am returning to Apple and BootCamp had me confused. It is nothing more than under OS X partitioning the HDD and in Windows loading all the drivers.
If installing only Windows then the OS X partitioning is not applicable so no hybrid HDD partitioning scheme is created. (Elsewhere I found references that a hybrid partitioning scheme is unpredictable and potentially unstable - I certainly have had my share of issues while experimenting different failure / backup / restoring scenario's.)
Having said all this, Windows 7 as the only OS on the Mac (no OS X) has proven to be the easiest Windows install I've done, all is there left to do (after the windows install DVD has done its thing) is to insert the OS X install disk (under Windows) and run the BootCamp install which loads all the Windows drivers. No hybrid partitioning scheme is created and this has the potential for being an extreemly stable environment. (and you finish up with an extreemly quiet and compact desktop with the Mac Mini)
A word of warning: If you remove the HDD with GUID partition (because you are replacing the HDD with a SSD or a 7200 rpm/16Mb cache) then do not try to manipulate the GUID on this HDD as an external drive. I lost the internal drive and had to reinstall. (I discovered GUID manipulation does not work on an external drive.)