Originally Posted by fetz
Windows does see the old registry and uses it. This is why some people have problems even after a reinstall.
No, it doesn't.
The only time Windows will reuse your registry is if you do a repair install. And even then, some core data is written fresh from the install disc. Essentially, only things that are added after the fact (applications, settings, etc) are reused.
You are, however, VERY correct in your statement that it is recoverable.
If you're a normal consumer, you can buy tools that will find usable data on your drive after a format or two (quick format makes it REALLY easy), provided it hasn't been written over physically.
There are companies out there that can recover data off drives that have been formatted multiple times. Or set on fire. Or hit with a magnet. OnTrack (the company I deal with for issues like this) can take drives from a RAID 5 set that have been physically moved around on the controller and rebuilt into a different array, and recover data from them. It's downright scary.
You don't even want to THINK about what a true computer forensics specialist has at his disposal for pulling the embarrasing porn off your drive...stuff you deleted a year ago
DoD/NSA standards are the only way to be sure. 7 pass wipe with bit-flipping writes are the way to go.