I like Diskeeper, but some others have had issues with it. Do not know what is in Jeff's recommended suite, but will look at that.
As for Nero, or Roxio, both seem to have gotten better, in that one has almost total control over which modules you install and turn on. In the old days, you were more at the mercy of the installation program, and had to really work to NOT install the full-boat, that can get in the way with things like Watcher/Sniffer apps, and InCD/DLA for packet-writing. I have Nero, but only installed the elements that I wanted. No issue with any Adobe program, Gear Video, or ImgBurn. I also like CyberLink's PowerDVD/BD and also MediaPlayer Classic HC.
Now, obviously ImgBurn and G-Spot are great utilities to have. I feel the same for a good bit-rate calculator. Looking around, those are my go-tos. Now, you are probably looking more for real "utilities," but I threw in a few others for good measure. Oh, and my beloved DigitalMedia Converter 2.7.
My opinion on Nero is that is it bloated and full of bugs although I last used version 6 (I think) when I was on Vista. Windows 7 has all the burning/ripping (mp3 via Media Player) capabilities built-in that personally I feel no need to use another software to do these. If I were to do back-ups of DVDs that I add to my collection I would use a utility like DVDFab Decrypter but will install it only on a Virtual Machine and run it from there, not on my local machine which I try to leave uncluttered.
So here is the list of tools that I use:
1. VMWare Player. Free player to run virtual machines on. With gigabytes of RAM on my PC, I can run multple OSes when I am not doing video editing. This comes handy on applications development where I run and interact with, say, a database server, a web server running off separate VMs, and a test Workstation running test scripts, all at the same time, all running off my main workstation. I also have another VM dedicated for ripping DVDs and for torrenting.
2. Microsoft Encoder 4 Pro and CamStudio (free - open source). For recording screen activity.
3. DVDFab. For backing up DVD collection.
9. uTorrent. Self explanatory.
7. HD Tune and Crystal Disk Info. To benchmark and monitor hard drive health respectively.
8. A couple of Windows Gadgets such as Intel's Turbo Boost Indicator (shows amount of turbo boost), GPU Observer Gadget (shows GPU temps, fan speed and activity), Sushi DriveInfo (displays internal, external drives and amount of space used/remaining).
9. EVGA's Precision Tool. To customize the fan speed of the GTX 470.