I just reformatted my six-year-old desktop a few months ago, because it was getting lethargic with the clutter. And I decided that this time, I will keep track of all the crap that loads up at startup and all the processes running from the beginning.
I also did some slipstreaming and made back up images of my hard drive from several different points in the process, such as 1. Clean Windows Install, 2. Clean Install + all Windows updates, 3. Clean install + all Windows updates + all hardware drivers + anymore updates, 4. All that + vital software.
The slipstreaming disc let's me load up a version of Windows called BartPE solely into memory from a CD, so that if anything ever goes completely wrong with my Windows partition on my hard drive, I still have a version I can boot from any CD-ROM. From there I can connect to networks and mess with the hard drive contents either from the same PC or from a different (working) PC on the network, or if I can't do anything to fix it then I can use BartPE to revert back to one of the backup images.
Anyway, I made a whole list of folders for the software I knew I wanted/needed, with the install files in each respective folder. That made things much easier to cleanly install exactly what I knew I needed and wanted, without forgetting something after it was gone.
The few I can remember off the top of my head:
1. Mozilla Firefox - duh
2. BitTorrent - my favorite bittorrent client
3. Nero
4. AnyDVD - for nefarious purposes
5. MS Office - duh
6. Photoshop - es niiice
7. Steam
8. Adobe Reader - or Acrobat if you have it
9. Adobe Flash Player - I think Adobe actually combines most of their needed downloads into one install exe now
10. BitDefender - I'm done with crappy free virus protection, I bit the bullet and bought a license for 3 computers for three years, I think for a total of $80. BitDefender is highly rated.
That's all I can think of at the moment.
11. Delphi 7
12. PCB123
are two more for me, but that's really for work purposes.