I used to agree with you, but it's just not that simple. If I compare the amount of time I have spent trying to get some piece of hardware that should "just work" in Windows, to the amount of time I have spent trying to get some open source driver working with a similar piece of hardware on Linux, they are really not all that different.
When Windows 7 x64 came out, the Windows hardware advantage pretty much went away. You may be lucky enough to have your old peripherals just work, but chances are good that something will break.
So no matter what OS you choose, you need to do research, buy the appropriate hardware, etc.
Now, that said, I can almost guarantee that that old scanner in the bottom of the closet which stopped working with Windows 2000, will absolutely work just fine with the most current Linux kernel.
