Slow browser at system startup with NIS 2009

I have Win XP SP3 and NIS 2009.  After I start my computer, after a couple of minutes I can normally startup firefox without any delays.  Since I've installed NIS 2009, when I try and run firefox, I have to wait a few minutes before it loads and is usable.  This is undoubtedly NIS 2009 causing this holdup.  Is this a known problem?  Is there anything I can do about it?

 

TIA.