like not high enough to have remote access...
i have vista home premium and 7 starter...that kind of low....haha. I do have another computer with xp though.
For your "Low Level" OS'es....I actually suggest Logmein Hamachi. Its will give you VPN access to the machines you want to get to and then you can use anything from remote desktop to vnc to actually connect to the machines.....https://secure.logmein.com/products/hamachi2/
And its completely free for "Absolutely free for non-commercial use"
I have Windows 7 starter on my netbook and I do believe that teamviewer should work on that.
I have been using teamviewer for the last three years and I've never had a problem with it. You can set it to start up every time your computer starts or you can also start it manually. Furthermore, you can set your own password or have the program generate a password every time you begin a new session. There are even teamviewer versions available for the iPod, for the iPad, and for the Mac. I have tested all three and they work great!