Win ME w/ Win XP Home Edition

I've two computers: Upstairs (new) hp pavilion a650y using Win XP Home
Edition, and Downstairs (old) Gateway, using Win ME. I use a Wireless
Linksys router w/ an adapter for downstairs to connect the two. I also
purchased Win XP Home upgrade, which is supposed to change the downstair's
Win ME into Win XP Home. I had many problems and it was suggested that I do
a clean install of Win XP. So, by using the Upgrade XP CD, I tried to get
rid of Win ME on the downstairs, and install only XP. The end result was,
for reasons I'm still not su First, I had to reinstall my router adapter
downstairs, because XP wouldn't detect it, then, after installation, my
wireless router kept kicking off line about every minute I'd lose the
connection. After frustation, I then re-installed Win Me by the Restoration
disks (specifically disk #2) of the three disks. Now, I have no sound or I
detect slight sound in the background that's a carry over from XP. Why would
that be happening when ME does, I thought, a completer format of the hard
drive? Anyway, can someone help me either get rid of Win Me, and format the
C drive, then install XP by the upgrade disk, or, now that I've re-installed
ME, find out why I haven't sound, correct it, find out why I was always
kicked off line on my wireless router, correct it, and either before all this
or after all this, re-install XP's upgrade, and in the end, have my
downstairs computer (Gateway), connected wirelessly to my upstairs computer,
both using Windows XP Home Edition, SP-2, and my wireless router/adapter
combination working well? Please help.