computer freezing with NIS 12 on windows 7 home premium, 2g ram

Main issue:

Just installed NIS 12 yesterday. Running with Windows 7 home premium, 2g ram. Computer is SLOW, Freezing frequently, running with high CPU usage. Having to shut down with power button.  

 

Also N Confidential plug in keeps crashing in google chrome. Read somewhere on forum to disable tool bar. Did that - not a very elegant solution.( Who's writing and testing N's software?)

 

Other issues:

Installed NIS 11 on 2/11 but required renewal within < 6m.

Renewal was supposed to be $49, but was $59 on Norton website

Bought NIS12 @ costco w3ith N utilities. Utilites cannot be activated with product key.

Can't believe I paid for all these issues/problems!!!!!!

Any SIMPLE solution to main issue before i get refund fron costco & get Kapersky?