I haven't tried to install PSP 9 on my Win7-64 machine but one thing I would do is to find the actual .exe file (right click the PSP shortcut and click Properties\shortcut tab\open file location) right click the .exe file and click properties.
On the compatibility tab check Run this program in compatibility for: and choose Windows XP SP3.
Next check Run this program as administrator.
If this doesn't work you may need to reinstall, doing the same for the installation program (running as admin under XP compatibility mode).
"Smoke me a kipper, I'll be back for breakfast."