Alright, instead of just listing the programs I like best I thought I would say why so some of them might help a few of you out. In no particular order...
Diskeeper 7
This is probably the most widely acclaimed third party defragmenting program. The defragmenter in Windows 2000 and Windows XP is actually a modified version of the lite edition of diskeeper. The full edition defragments much faster than anything built into windows, and seems to do a good job.
Winace 2.2
Winace and winrar both stand head and shoulders above winzip. One is just as good as the other for functionality but I prefer winace due to its more elegant interface. Oni, if your talking about it not being able to extract winrar 3 files, that functionality has been added with version 2.2
NERO Burning ROM 5.x
This is by far the best overall burning software available. It frequently gets updated with new features and bug fixes. For some burning jobs, other programs are better (Fireburner for CD image burning for instance) but no burning program does as much as NERO does.
WinMX 3.xx
If it’s been a while since you've used WinMX try it again. Before the version 3 update you had to totally baby-sit your downloads since there was no auto find sources or multi downloads. Now there are both. You get better / more search results than with Kazaa and the official version comes with no ads or spyware right out of the 'box'!
Exact Audio Copy
The best audio CD ripping program available. It is highly configurable and has a nifty secure ripping mode that can find the truth among whatever multitude of scratches you've inflicted on your CDs.
LAME mp3 encoder
Not really a program, but when used in concert with Exact Audio Copy you'll be ripping CD's and encoding them to MP3 with the best of them. Death to the 128-bitrate MP3!
Folding@Home
This program gives you an excuse to buy the latest and greatest hardware and motivation behind those last few MHz you manage to get out of your CPU. Stanford, with the help of the folding community, is researching protein-folding simulations. It’s your chance to do something good for humanity. If you've ever know anybody that has had a un-preventable degenerative disease (I'd type a few out but I have no idea how to spell any of them) then this is something you should be doing.
Norton Antivirus 2002
The top dog in Antivirus, I'd be embarrassed to say how many times this program has stopped virus' from getting on my computer.
TMPGenc
Have a DivX or other kind of digital movie on your hard drive and you want to watch it on your standalone DVD player? This is a great tool for converting various formats of digital video into... well... other various formats of digital video. Including VCD & SVCD. This program is very useful if you don't like sitting in front of your 13" monitor for hours at a time.
Okay thats it, could keep going but I'm tired 
