I think Gozilla is the one behind all these. Do you have any problem deleting gozilla and not use it any further because just like dm.su said it might be supporting spyware/adware. Not just gozilla there are a loads of program out there which supports spyware and adware.
I think the reason why your comp is freezing is because there must be hidden spyware and adware.
And i would say Norton is the best. How come the norton is not detecting anything. Did you keep it up to date. ON the top left corner of the norton Live update will be written. you got to live update it regularly to keep the norton updated.Did you ever try that.