As long as your OS (Operating System) is fresh and clean, you should consider installing some programs to help you out on your computing adventures. In the last post I asked "what will you use your PC for ?", and explained what I use my system for, I will go into further detail of most of the programs I use.
For my collection of digital music I use Winamp, which can parse a crapload of mp3s into a concise and easy to use library which is searchable. You may obtain winamp @ http://www.winamp.com for free, as well as a paid version with more features(that you probably don't need).
Combined Community Codec Pack
I use the CCCP for the codecs it contains, as well as the Media Player Classic that comes with it.
You may obtain CCCP @ http://www.cccp-project.net/ for free.
I use Tor for anonynimity purposes, see my post about tor for more info.
I use Firefox due to preference mostly. Check it out @ http://www.getfirefox.com
torbutton can be installed in it for easy and safer browsing.Chatzilla is also nice if you want to lurk in the IRC areas of the internet.
Technitium MAC address changer
A great tool to change the MAC address of your network interface.
get it at tmac.technitium.com/
TL;DR A short example list of programs I use on my PC, to help the reader get a better idea of what they need for their purposes.
Post any questions and I'll try my best to respond.