Instructions on the upgrade procedure:
You SHOULD follow the step for “A quicker installation†because I had a blue screen issue when I upgraded from the CD but not when upgrading from the hard drive (reading this post just reminded me of that issue) . Number 2 & 6 are very important (security measure).
Windows XP Home & Professional are the same program. They are both known as Windows NT 5.1 or build no. 2600. The reason that they have different names is because XP Home was stripped of some features that remain in XP Professional, but the core components are the same. The upgrade process is actually quite smooth because of this.
Although it’s usually better to do a clean installation, I found it not to be the case with the TR.