Installing Windows ME over ME usually tends to not work
out so well, Windows ME tends to give you errors.
Formatting with fdisk, then installing, is the best way,
but then you will lose all of your data. But after a few
years, Windows just kind of gets to the point where you
really need to reinstall it, I've been there........

My advice would be to back up your data, onto a CD or
floppy disks, make a Windows start-up disk, format your
hard drive, and then reinstall Windows. Or mabye you have
a reinstallation CD that came with the computer that will
do all of this for you.

Here is a link that will tell you different ways to
reinstall Windows, some of them will let you keep your
data, other won't. They all have their advantages and
disadvantages, so it's your decision.

http://www.windowsreinstall.com/install/waysofreinstalling
windows.htm

Here is how to reinstall ME on most major computer types:

http://www.windowsreinstall.com/oem.htm

There's a lot of helpful links on this site.

Good Luck!