If you have CyberDefender on your system, I would advise you to uninstall it as it is RogueWare. The majority of the erros it found if not all of them are most likely false, to trick you into paying for the program.
Uninstall using Start > Control Panel > Add or remove programs.
After you finish uninstalling it, run MalwareByte's Anti-Malware and SpyBot-Search & Destroy. This should hopefully take care of any problems caused by the Rogue and clean up any problems you may have been experiencing before hand.
The easiest way to help prevent infect is to keep you system completely up to date with Windows update and to keep all the software on it up to date so as not to present any security holes to any drive by installs when you're surfing.