Hi Bryan - Are you just asking for descriptions of what these options are? If so, please just go to the Help menu and select Contents (or hit F1) and find the Node Reference section and look under Model for the Gradient Boosting Node.
In particular, you will want to control the number of iterations and the shrinkage parameters primarily to drive how quickly and effectively it converges. The defaults are set based on what we feel is a good balance between accuracy and speed...but of course you will need to determine this based on your own problem.
Hope this helps.