Oy vey! You are mixing up a few things. Your subject line says 6.22 and your
body says 6.2. Different things.
As far as I can recall, 6.2 was an update for 6.0, 6.22 was a standalone
version of MS DOS. So if you indeed do have DOS 6.2, you'd need 6.0 already
on your computer. If you have 6.22, you can install directly. And yes, I
think you'd be safest doing it from floppies because it would probably
prompt you to insert the next disk. I'm not sure how you'd navigate through
that with a CD.
http://en.wikipedia.org/wiki/MS-DOS
If you really get to the point of installing 6.22 look at this:
http://www.windowsreinstall.com/install/msdos/install622/page1.htm
Keep in mind that although MS DOS is obsolete, MS is still pissy about
anyone using it without buying it, as has been darkly hinted at here. So if
you just want it to run obsolete games on a standalone computer, why not use
a freeware DOS? Look at the Wikipedia page for FreeDOS or DR-DOS.