XNA\MonoGame will get you up and running almost over night but I would not get to deep into XNA because while I loved it and it was awesome to get me started by the time you are good with the API you will be wanting to move over to sharpDX, then have to unlearn heaps of stuff that XNA lets you do and get used to the power DX11 brings.
I came in to XNA just before they dropped support and I wish I had moved to sharpDX sooner because its a bit harder but I found that having to write all my own tools and framework to be very rewarding.
I use the sharpDX toolkit for all my 2d stuff and raw sharpDX for the rest, the toolkit also looks just like XNA so moving to the sharpDX toolkit is easy once you get your head around XNA.
SharpDX.Toolkit
My point is, use XNA to get your feet wet but don't get to locked in and move over to sharpDX as soon as you can.
Because not many ppl seem to do fun stuff with VB.net you will have to convert the XNA samples from C# to VB.net and there are some parts of sharpDX that need to be changed in order to work with VB.net.
I know sharpDX seems like a lot of work, it is but its worth it in the end.
GitHub is your friend and the sharpDX dev is a beast and knows his shit, I'm also proly going to add a VB.net repo for sharpDX to my GitHub(at some point).