Confidentiality, integrity, authenticity and Privacy is perhaps the most important aspect of computer Security for everyday Internet users.
Security becoming more complex and it is crucial to the protection of critical computing and communication infrastructure.
Various approach need to be taken to address the problems, ranging from purely technical issues (e.g., intrusion detection, network security, etc) to ethical.

Some general tips that I can recommend as follows:-
* Apply vendor-supplied software patches in a timely manner
* Disable features/services that are not explicitly required
* Install anti-virus software and keep it up to date
* Use caution when opening email attachments and following URLs

Below are some utility software for detection:-

MWAV, is a free scanning tool only scans for viruses, however, it does not have the capability to clean it.

VIEWTCP is a free network monitoring tool to monitor various ports on your PC and the remote network addresses suspicious applications are accessing. Click on the icon to download.