The best way to get rid of a virus is not to get them in the first place by running Internet Security Software. My favorite is Kaspersky Internet Security, I've never had a virus and I go on all sorts of websites.
Since you already have a virus, here are some things that you can do to get rid of it:
First, buy a professional anti-virus software program or download a free one. My favorite free anti-virus software program is AVG Antivirus.
If you cannot install a software program because the virus is so bad, you can try an online virus scanner. My favorite is Bit Defender's online scanner. It is free to use.
Free Online Virus Scan
Sometimes viruses turn out to be a result of something other than a virus like Malware, Spyware, or Adware. These nasty problems are not always caught by anti-virus programs, so you may need a combination of an anti-virus program and Malware Bytes (also free) to get rid of your problem.
Malware Bytes free edition
Free Anti Malware Malware Removal
Good luck to you!