My Top 10 most recommended software.
1.
CCleaner - is a system optimizer and cleaning tool, it makes your computer faster and more secure. It also cleans traces of your online activities such as your Internet history. Additionally it contains a fully featured registry cleaner. But the best part is that you can download it for FREE! You will be surprised at how much disk space it can recover - in fact, it managed to clear out 850+Mb of crap from my PC when I first use it. Now, I'm using it on a regular basis to keep my computer clean and safe.
2.
Microsoft Security Essential - this anti-virus is totally free for all those who have a genuine windows operating system. It protects your computer from virus and malicious softwares. It has a real-time protection and it didn't slow down your computer unlike any other anti-virus.
3.
Google Chrome - fastest web browser ever! I've tried different kind of web browser but none of them can beat Google Chrome. Also, there are many cool stuff on this browser such as: extensions like WOT and AdBlock that help prevent visiting dangerous websites. You may also synchronize your bookmarks from your google account so you don't have to bookmark the same website on another computer that you are using.