I have had experience with several antivirus software, including McAfee and I was never spammed.
It would be wise to download and run this software:
Download the following Adwcleaner created by Xplode
Launch it (for Windows 7 and 8, click right to run as administrator)
Click on delete
Post the log C:\Adwcleaner[Sx].txt on this thread.
Certainly in the future, for your security, I would stay away from not only McAfee but also from all Norton Symantec products who will charge you a fortune to disinfect the computer you paid them to protect.
Kieferchild suggests Nod 32, I use F-Secure and Kaspersky is also recommended.
Moderator, Virus/Security Contributor