Whats the best program?

Hey guys i finished building my comp and its all good.. i get around 4000 in 3dmark 06.. i think cuzi never OC it but is that a good score? anywys how do i over clock using programs? i need to know whats the best programs out there for all computer stuf and to keep my comp safe? so far i have

Windows Media Player 11
Fire Fox
I Tunes
Quick Time
Limewire
Winrar

i just finished it yesterday so i had a few time to download those and had to transfer files from my old comp to this one. anyways what are some must get progrmas out there? like best virus scanner , best bit torrent , best video player and so on. i dont mind using multiple video players or audio.. i just want the program that will play ALL videos and audio files on the net. i really like itunes i got used to winamp should i still get winamp? and i might get vlc media player.. theres lots of program i dont know about like cpu cooler temps and computer monitoring and so on.. so whats the must get progrmas out there ?