Good enough Internet Security Suite?

What is a good enough Internet Security Suite that won't slow down you computer but protects really good?

Thanks to those who give a decent answer.

Good enough Internet Security Suite?hijackthis

Norton Internet Security is a comprehensive firewall and antivirus program.

Good enough Internet Security Suite?malware

kaspersky internet security suite is the best ever , best firewall , best antivirus , REAL protection , i had norton internet security before , it's really bad , it lets everything in , i found tons of spyware and viruses when i installed kaspersky , also , it doesn't affect the computer's performance.
PC Tools AntiVirus Free Edition feature highlights

Protects your PC as you are working, surfing and playing

Detects, quarantines, disinfects and destroys Viruses, Trojans and Worms

OnGuard鈩?protects your computer against threats in real-time

Automatically checks for frequent updates against the latest threats.

http://www.pctools.com/free-antivirus/

*Never install more than one anti-virus on your PC, as they may conflict with each other. On the other hand, its always good to install more than one anti-spyware.