Below are the generic installation instructions and yes it can be done in 20 minutes if you already have spent the time lining up all your ducks in terms of information and pre-requisites
Here is a list of some of the top new features in XenDesktop 7.
Installing your Site on your first XenDesktop 7 Controller
1. Run AutoSelect.exe and install any pre-requisites that are not yet installed to enable the installer to start.
2. Click on Start