I'd like an SSD, but I've read a few bad things about them. Basically, they're not as reliable as they could be (as compared to SATA or PATA drives) and when they fail, you're screwed. At least with an SATA or pATA drive, one MAY be able to salvage the platters and install them in an operating drive. Check out Newegg or 3bTech. I've seen them on sale lately.
Hardly, at worst XP 64 bit, more than likely Windows 7. I kind of like Windows 7 and all of the stuff is certified for it. There's a thread where I laid out the specs for my motherboard, case, etc. http://www.conservativecave.com/index.php/topic,45798.0.html
The proc is an AMD Phenom II X6 1055 (the slower and cheaper one) and the RAM is 2- 2GB sticks of Super Talent DDR3 -1333
This is why I bought the Thecus
NAS to hold my archive data. Windows 7 will automatically run the SSD TRIM to keep the data defraged so I have no worries if I lose the drive. Since the late 90's using NT, I have always stored my sensitive archive data on a seperate hard drive and burning the most sensitive stuff (pictures of my cats - it's a wife thing), on CD's.
The best part of using an SSD, aside from the shear speed, and using a NAS, I have actually removed eight hard drives from my systems, changed from 1K watt power supplies to 450 watt power supplies, dropped the temp in my computer room by 3 degrees, and cut 10 bucks off of my monthly power bill. Believe it or not, that 3 degree temp drop is a huge thing.
ETA:
You are correct about salvaging dead drives. I have swapped the circuit boards and platters between drives (Torx tools not with standing), to resurrect them. Do you remember the old freezer trick?