Moved this to Malware Discussions.
Can you use System Restore to go back to before this all started? If necessary it can be invoked from Safe Mode.
If not try scanning with some extra tools - see the last link in my signature below.
Perhaps Stinger and Malwarebytes Free. To keep the latter free of charge do NOT accept the free trial offer.
The "IHaveNet" browser redirect is well-known and all the forums are full of complaints about it. Amazingly their website has a Green rating on both SiteAdvisor and WOT.
The first step is to check Firefox add-ons for anything that's been installed without permission, and to look in the list of programs on the PC for anything that shouldn't be there. Task Manager or Process Explorer should show any rogue processes, and AutoRuns will show all the programs and processes that run at startup and login.
AdwCleaner might be useful here, and so should Malwarebytes.