Here is some useful software and drivers for your PC. All are certified virus and spam free software. A good thing is FREE TO DOWNLOAD AND USE.
One can download and install software as much as he wants, Although softwares are clean and free of bugs from many reputated developers, but it is suggested not to overload your pc with unnecessary programs. It may result in slow ones pc. The thumb rule is "Before loading think about its requirement".
Below are some good reputation sites where one can go for software search:
http://filehippo.com
http://www.filehorse.com
http://www.filecluster.com