Software Protection

I recommend that you have good protection and utilities like: anti-virus, anti-spyware, and using safe browsing techniques such as a pop-up/ad blocker.

Anti-Virus recommendations

Bitdefender – (fee) – leading protection for your computer
Avast – (free) – has a large user base and security updates are often uploaded
Avira – (free) – somewhat slow with security updates but doesn’t require a lot of resources

Anti-Spyware recommendations:

SuperAntiSpyware
Malwarebytes

Web browser recommendations:

Firefox ((recommend installing as an extension/add-on the free Adblock plus subscribing to both Fanboy’s and Easy lists.))
Chrome ((recommend installing as an extension/add-on the free Adblock plus subscribing to both Fanboy’s and Easy lists.))
Opera ((recommend installing as an extension/add-on the free Adblock plus subscribing to both Fanboy’s and Easy lists.))

Utilities

CCleaner
SpeedFan