How many times?

My PC had been in trouble for weeks, and I finally decided to reinstall it. It was actually not my PC but Windows XP that was in trouble. It was so slow that it took almost 15 minutes to start the system. As I had a whole image back up of the hard disk, it should have been easy work but not. The image back up was made almost a year ago and there were quite a few application and data files created since then. Plus, the system itself had a lot of security patch and I had to restart the system more than ten times to install all the updated files. As I don't have a broad band connection in my house, I had to do all the jobs in a comic cafe. It took almost two days to finish the re-installation and I've read dozens of comics during the waiting hours. Now my PC is moving quickly and I'm happy, but I hate reinstalling PCs because it is a waste of time. Thinking about the hours spent for reinstalling PCs all over the world, this incompleteness of Windows is almost a sin.