Download and run the McAffee tool from here http://download.mcafee.com/products/licensed/cust_support_patches/MCPR.exe

Download and run the Norton tool from here https://www-secure.symantec.com/norton-support/jsp/help-solutions.jsp?lg=english&ct=united+states&docid=20080710133834EN&product=home&version=1&pvid=f-home

Reboot on completion of each run

Once done let me know if there is an improvement