I like the way you put that. Every program that loads when you boot and stays in memory slows your PC just a tiny bit, and increases the odds that something won't work properly. So it's best to assume that you should probably disable most of them.
I'm not talking about software you don't want at all, which is a whole other issue. I'm talking about programs you want to keep, but don't have a legitimate reason to always run in the background. Personally, I like WinZip and Photoshop, but I don't need little pieces of them running at all times.
What should you allow to autoload?
More - PC World - What Autoloading Programs Should I Keep?