free, excellent software:

Open Office
free PhotoFiltre , a powerful graphics editing program.
Faststone Image Viewer, and several other programs. This is an amazing newish program that is becoming a freeware standard. It will do many photo editing tricks, plus displaying almost every image format.
VLC media player. VLC will play almost every media file...video, audio, and will even do jpegs as a slideshow....take a look here at its features It will NOT play most Real Audio files...for that you need: Jet Audio, which will play almost everything VLC will, and Real Media files also. Its only real limitation is converting/encoding MP3s.

Or, you can get Media Player Classic, which is a vast improvement on "Windows Media Player" that is supplied with Windows. It does 'almost' as many things as VLC & Jet Audio.

but...whether you get any of the above, you should have Irfanview, a renowned free media-graphics program that will show/play almost any image or video except RealMedia.

Then for using a PC computer everyday, it is a good idea to have a file management program that is more useful, powerful and sensible than "Windows Explorer".

Take a look at:
[xplorer²]...has a free version.
or perhaps Free Commander, which is a bit simpler, but quite powerful.
There is even FileCommander, which will do about the same as the other two, but can have 4 'panes' instead of two....

Then, for **SECURITY** there are free antvirus progs like AVG-free (excellent..updates itself on autopilot if you wish)...I have used it for 6-7 years now.

and for a firewall, I recommend Kerio..NOT version 4.X, but version 2.1.5, as it does the job without bloated extras and complex interface. Many, many experts have tried version 4, and gone back to version 2.1.5.

There is another free firewall called SyGate, which seems to be pretty good also...I just have had no reason to try it.

for spyware management **GET** SpyBot Search & Destroy ..'nuff said!

There are so many other little special purpose programs...font viewers, spell checkers, thesauri(??), email, newsreaders, news aggregators, download managers, Personal Info Managers (for addresses, schedules, calendar...etc..), alternative browsers (Opera, Firefox, K-Meleon), Capslock controllers, screen capture utilities.......on & on & on...

I, of course, have WAY too many and don't use some very often, but it's a hobby, and the ones I DO need keep me safe while I play with the others..*grin*

more info on request...