Constrain Proportions grayed out in PSP CS2

I recently got a new machine that will be dedicated to Photoshop, related programs and printing. I installed CS2 9.0.2, activated it, and now if I go to the 'image size' dialog box the 'scale style' and 'constrain proportions' are grayed out and the 'constrain proportions' box is ticked. Because the two options are grayed out, I can make turn the options on or off and I can't change 'width', 'height', or 'resolution' independently of each other.

I did copy my 'prefs' from the old machine and have a number of plug-ins installed, but the identical ones that I had on the old machine.

Both machines are running XP SP2 with latest patches.

TIA,
Jim

Check the "Resample Image" box.

Of course, many thanks for pointing out what I should have seen.

Appreciate it!!!

Jim