Well firstly I'm not a McAfee or Norton fan so I won't even go there.
I'm assuming you probably have another computer available to you. What I'm going to advise that you do is to go to a web site and download some really great programs that should clean up your pc.
Once you have them downloaded you'll need to copy them to a flash drive/memory stick or burn them onto a CD (or DVD as long as your pc has a DVD drive in it).
When you get to this website there will be some tabs at the top of the page. Click on the "Download" tab. Use the search box and locate the following programs and download them either directly onto a flash drive or to a folder on the computer so that you can burn these probrams onto a CD later.
Here's the website: http://www.download.com
These are all FREE programs and you may need to include the word "free" when you search for them to find them easier.
1. Advanced System Care Free
2. Malwarebytes
3. AdAware Free
Once you have them downloaded and on a flash drive or CD you will need to install them one at a time and run each one as you install them. I recommend that you install them on the infected pc in the 1-2-3 order I've stated above.
ASC should run in under 20 minutes unless you have a really badly fregmented hard drive.
Choose to run a "FULL SCAN" on the next two.
Malwarebytes "full scan" will take an hour or so to run a complete scan on a really messed up pc. So walk away and let it run. Once it completes, let it delete everything it finds and dislikes.
Adaware "full scan" will take about an hour and a half or more to fully analyze every little recess of your pc. Again walk away and let it do it's job. Let it delete everything if finds and dislikes.
Once you have run all three of these programs, DO NOT reboot your pc yet. What you need to do next is to "turn off the System Restore function in Windows" first. This will delete all the previous old restore points that most likely still contain any spyware/malware that is on your computer.
CLEARING THE SYSTEM RESTORE UTILITY IS A CRITICAL STEP IN CLEANING UP YOUR PC!!!
You didn't mention what you are running for an OS. i.e. XP, Vista, Win7 so I'm going to preclude giving you step by step instructions unless you write back specifically needing them. Do this instead at first. Click on START and then on HELP/Support in the little menu. Once into the HELP area type in System Restore in the Search Box and see if you can find instruction on how to turn it off and back on.
What you'll need to do, is to TURN OFF System Restore and then Reboot your PC.
Once you have that done, then you can trun the System Restore function back on again.
This will delete all the old restore points when you shut it off and reboot and it will allow a new Restore Point to be created when you turn it back on.
As a last recommendation, I'd suggest you get rid of McAfee and go to the Microsoft.com site and look for the security tab at the top of the page. Click on Security and then on Microsoft Security Essentials. It's much better that either McAfee or Norton and it will warn you if you go to a bad page or is you are under attack. Give it a shot. I've been using it for 2 years now and wouldn't ever go back to any of the others since they are full of bloat and simply dont work as well. Also, with MSE you can schedule when it will run in the Settings area.
Hope this all helps you out. Email me if you have any further questions.