I use realVNC which is free although I also recommend their enterprise product (for security and file transfer capability). The size of the software is extremely small and it uses almost no system resources.

I have a dynamic IP address at home (meaning the IP changes every so often). I registered a domain name and then use DNSexit.com's free software to update my home computer's IP address every X minutes. There are many services that will accomplish the same goal here but I highly recommend using VNC.

When you use one of those website companies you are required to rely on them to make the services work, plus you are allowing them into your computer if they so desired. VNC is completely independent and you are not relying on any 3rd party to keep your data safe. VNC also has the ability to access the PC from any web browser without the need to download the client software (although the client software has more features than the web version).

Accessing a remote desktop can be a bit complicated...if you need any help setting it up, I'd be happy to lend a hand.