The devil is in my system! Outwit my hacker please??

Hi all,
I really need help. I am about to lose my mind. I could write for days about my frustrations, suffice to say that I have a serious problem, and from everything I have read and researched, it is clear someone has broken into my system despite all the security precautions I have taken. I have performed factory restores on my system from my computer partition, and I believe that too has been compromised. User account names and permissions have been altered, strange new files occuring on my computer, and I am grayed out of several areas. Reading the logs in task manager is really interesting, all kinds of strange things happening. Services that I turn off turn back on. This is a personal laptop, I should not be networked, I use a wireless router with WEP. I feel like I am battling with someone sitting out there at a computer attached to mine. I just finished running all of the requested items in the what to run and do for malware-the guide. I hope there is someone out there with the knowledge and expertise to help toss the devil from my system. I believe I have a rather sophisticated hacker here. This has been an ongoing all consuming nightmare for me, and for all my efforts I have utterly failed to find a solution.