Computer unresponsive after wake-up

Ever since I installed NIS I have no control over the PC many/most times when it wakes from sleep or hibernation.  This occurs with Vista and also Windows 7, laptop and tower.  I cannot tolerate this - at the office (laptop, Vista) I have to wait up to five minutes sometimes before I can print out a customer invoice.  At home, (tower, Windows 7) I just sit and twiddle my thumbs waiting before I can do anything with the PC.  I run a synchronized-to-music Christmas display from the home machine and absolutely can't have even the chance that Norton will think it has permission to take over my machine.  How do I eliminate this boorish behavior by NIS?  Thank you.