[proxy_user]

A ordered a nice recent-model Dell Optiplex with Win 7 installed on eBay. Only $180 shipped, should work.

Your other choice is to install Linux immediately, but I need at least one Windows machine.

[doorgunner69]

Just started using Win 7 and find it just fine. Similar enough to XP to be not the disgusting jolt that the wife's Win 8 machine is.

Different, yes, but no problem. Do not ever see using 8, with any luck 9 or whatever will be workable way down the road.

[Bloody Sam Roberts]

Your other choice is to install Linux immediately, but I need at least one Windows machine.

Run VirtualBox on XP and install a Linux distro on a VM.
Then setup the VM to bridge to the NIC. You can then disable TCP/IP on WinXP so it can't be reached via the internet. The Linux VM will get that job.

You can use Firefox and keep your XP. I've been using XP this way for a month or more and it works great. And it's free.