If you use a computer for nothing but internet, redoing everything will only take about thirty minutes
Asphalt - this may be true if you don't take the time to do all the updates, or if you have an install CD with all the patches slipstreamed onto it.
If you are starting with an original XP installation, it can take about 6 hours of update & reboot, update & reboot, update & reboot just to install the critical patches. If you are starting with SP1, it's about 4 hours.
If you don't do this, in about 12 minutes, your computer isn't yours anymore, and you've now become an active part of the problem.
BTW, my wife and I *love* your "forty reasons not to post your photo ..." work on your "About Me" page. Brilliant!