Back in 2007, I started having problems with an IBM ThinkPad. After two system reloads and tech support telling me I had to spend a bunch of money to get a RestoreCD, I decided that it was important to make my laptop easy to break down and bring back. So I started looking into software that didn't require an install, and mostly left the computer alone.
At the same time, I was doing tech support on the side and started coming across more and more tools that would help me. The great data recovery tools to get back files that were deleted or corrupted were a huge hit both just because I could occasionally fix things considered unfixable or undo my own mistakes.
I also liked being able to take my computer with me, whether on CD, DVD, or flash drive.
The whole thing really began with an excellent launcher program. Most importantly, the menu system for all of this software was critical. You can't just create shortcuts in Windows because those change depending on what drive letter the program is assigned to. It needs to behave the same whether it's in your CD drive (usually D) or on your flash drive (usually E or F).
Although there were a variety of programs available to do this, the best one I found (and still use) is something called PStart.