Since I've found it can have a massive effect on some utilities -- like CCleaner cleaning up temp etc files -- I wonder if next time you might try Disable AntiVirus Autoprotect in the right mouse click on Norton task bar icon might help (remember to re-enable it afterwards).
Doing this with CCleaner makes the initial Analysis almost immediate whereas with that check enabled it can take minutes just to scan the drive and locate the files.
I imagine this is because Norton is assessing every file access the CCleaner makes.
This is on Windows 7 Home Premium 32 bit with plenty of spare disk space and 4GB of RAM ....
FWIW