Can I Share Programs Between A Windows 7 And Windows Xp Dual Booting Machine?
Here’s the thing, I have Windows 7 Pro installed alongside my Windows XP install. Both systems recognize each other as they are both NTFS formatted. My question is whether I can point to programs installed in either or?

Only way it would work is if you reinstalled it in the same location in the other O/S. You have to make the same registry settings and add the same system files in the same location for both O/S.
It may screw up one of them though because of changes in folders. I expect that your main Win7 disk is C when it is running but D when you are in XP. So, when installing in Win7 it may change the application files to point to D – which is not what you want for XP.
In short, no. Some programs will work, very small ones with minimal to no registry keys. The files are all there, but the registry keys from your XP programs aren’t on your windows 7 partition.
For example, audacity will run, but photoshop will not.
Just install the programs you need onto both partitions. Good luck.