To reiterate I use UltraVNC. Dynamic IP addressing is not a concern of mine since all my systems are on my local network. I have used TEamViewer but it was a hassle to use as it kept timing out while I was servicing my sister's Toshiba Laptop.

For the sake of completeness since I mentioned the free DynDns service, I will go through the process of creating an account with them and test it. I will report the results in a day or two.