teamviewer is the easyest way to do that
http://www.teamviewer.com/
its very very easy to set up jus launch on both ends and enter the ID and the password and it conacts and instantly schows you whats on the pc and it works very smooth
i think you can also set it up to run at startup so you can do stuf like restarting the computer ect...
logmein is a more complex one ut it has more options
https://secure.logmein.com
windows has a build in tool to but i don't like it that much