I am the tech support for my family, so I do a lot of installing of Windows on pc's. Here is a nice little list of must have freeware programs for your new Windows install!
Mozilla Firefox:
Need I say more, simply the best browser out there. It may not be the fastest, but it certainly has the goods when it comes to extensions, and website support. Mozilla made alternative browsers popular.
Alternative: Google Chrome, Apple Safari, Opera
Link: http://mozilla.com
Avast Free Anti-Virus:
You simply are stupid if you don't install anti-virus on a Windows system. Simply put, Avast will give you decent protection against those millions of Windows viruses, and best of all, it does it for free! I like Avast because it is light on system resources, and doesn't have that nasty link scanner that AVG has (it really is a server killer that technology).
Alternatives: AVG Free, Panda Cloud, Avira, ClamWin
Link:http://www.avast.com/free-antivirus-download
OpenOffice.org:
I still don't understand why people even bother using Microsoft Office. MS Office always seems to release new versions that alienate it's older versions of document formats. What does that mean for the average user? Well, it means if you write something now in MS Office, there is no guarantee that it will work in a few years. We have already seen it happen a few times before. OpenOffice will open and modify those MS Office files, as well as save documents in the Open Document Format that guarantees future compatibility. OpenOffice also opens older MS Office documents better than current versions of MS Office.
Alternatives: AbiWord
Link: http://openoffice.org
Izarc:
Izarc is a nice Winrar clone, and it's free. I use Izarc over 7zip because I feel that it has better dialogues in Windows, and has an easier to use interface. It pretty much opens every type of compressed file out there, even ISO's. Best yet, it's a small unobtrusive program.
Alternatives: 7zip
Link: http://izarc.org
The Gimp:
The Gimp certainly isn't the easiest to use program, but it has the goods when it comes to power and features. Gimp is basically a photoshop replacement, and will allow you to edit photos, and even make other digital imaging stuff. It is a little resource hog, but the feature set alone will ensure that whatever you need, the Gimp can do it.
Alternatives: Paint.net
Link: http://gimp.org
Pidgin:
A nice Windows messenger replacement. It supports other formats too, such as Yahoo chat, Facebook, and other popular chat protocols such as Jabber. It doesn't present any ads, such as Windows Messenger, and is not susceptible to MSN viruses (which is a very common thing).
Alternatives: Digsby, Miranda IM, Trillian
Link: http://pidgin.im
VLC:
If you want to play pretty much ANY movie/music format out there, VLC seems to do the trick. You don't have to worry about codec installations, VLC just works out of the box. It has a fairly complicated interface for newbies, but double click any file, and VLC will play it.
Alternatives: no such thing
Link: http://videolan.org/vlc/
Songbird:
A great Windows Media Player/I-Tunes replacement. Built on Mozilla technology, Songbird is the next step in the evolution of media players. It now supports CD-Ripping, so there is almost no excuse not to use this program.
Alternatives: I-Tunes, Winamp, Foobar2000
Link: http://getsongbird.com