Do you have administrator privileges on the user account you are logging in on?

Control panel-User Accounts, in here it will show if your login account is an administrator account or not.

It will say "computer administrator" under the account name

I would go into zone alarm and disable the " load at startup" and reboot and try it Itunes again

Do not just try to exit zone alarm this will not work..

Yes I am shown as the Computer Administrator.  What should I do next?  Thanks in advance for your response.

I went as far as to remove Zone Alarm and rebooted.  I also turned off the AVG Control center (I tried it with AVG on and AVG off) but I had the same results as I received  another "An error occured while updating the default player for audio file types. You do not have enough priviledges for this operation" message.  I also tried to change it again from The set program access and defaults area and it once again it started then stopped abruptly.  Thanks for any other suggestions.