Well those things found are nothing much.
By far the best explaination is a piece of HP crapware doing this too you. The chance of a virus changing your home page to HPs website are astronomically small
In the old days HP would ship with it's own customized verion of ie! Thank goodness those days are gone.
But try my previous suggestion of mssconfig.exe. It has to be some piece of HP software. EIther in your startup, or possibly installed as an IE addon. you can look for IE Addons here from IE itself from Tools->Manage addons in the IE menu bar. If you see somthing in there like "HP blah blah.." then disable it
Edit:
P.S. Though this acts like a contracted "virus" there is very little chance that any antivirus is going to touch it because it really is a "legitimate" piece of software installed by the manufacturer