I'm not exactly sure where you got your information on XP, or what your experience is with it, but I would not classify a 1GHz pc with 128MB of RAM a GREAT setup for XP. It is a minimal setup for usability. It will work, but not with any kind of speed. On the other hand, XFCE or fluxbox window managers on Linux will be quite happy with that hardware. To be REALLY fair, no modern system will be blazing with those specs.
Also, I don't know when the last time you did a Linux configuration was, but it is far more simple than it was a year or two ago. I have not had any of the "massive, time-costly research" that you indicated in any of my many installs this year.
As soon as people agree that every OS sucks, we can get on with our lives and forget this petty bickering.