Failed to Connect to a Windows Service

All of a sudden my computer is showing signs of a virus/malware and I do not know how to correct it. I have Windows 7 which takes a long time to boot now. Then when my desktop opens up I get an error bubble "Failed to Connect to a Windows Service." Lastly, while no programs are open, I all of a sudden hear audio of 2-3 different ads.

Please Help! :(