Do not like Vista

I was visiting my sister this weekend. She got a new computer, a HP Pavilion Slimline s3100n Desktop PC. Really nice machine. Only one major flaw with it, it came with Vista installed. What a terrible experience. I tried to help her set it up, but seemed like every time you tried to run or install something it would pop up a message asking you do you really want to do this. Of course, I did. I double clicked on it. Almost every piece of software she had on her old XP box would not install on the Vista machine. Had trouble getting the hardware (printers, camera, etc...) to work. After a day and a half fighting with Vista, I do not think I will be upgrading anytime soon.