Can't help you with desks but with chairs the best ones I've found are from Herman Miller. Many praise the Aeron chair and while it's great I found the Mirra suiting me better, try both of them out as well as their new ones.
Regardless of which one you pick, if you find one that's perfect - get...
As said, if you really care about removing your data and you really want to aid charity, zero the drive and install Ubuntu - it'll be faster, more secure and won't cost you anything but time. You'll also ensure that all licenses are in order and things working as they should (the basics at...
If you're playing games on it too you should take large installation requirements into account as well (GTA IV recommends 18GB of space for example). Went with the Corsair Force F120 for my HTPC.
I have the V1200B and it's a great case. The things I'm missing are vibration dampers for the HDDs and a removable motherboard tray, but it's still a good case. I have a Ninja installed and it fits nicely.
You can remove one of the HDD "racks" if you need more room for the PSU.