I think that depends alot on what type of game you want to create. For instance making a solitare, or dominos game in visual basic should not be all that difficult. The main difficulties come in to play when you want to do an action game either RPG or Arcade style then while it is possible you need to be very creative in your use of buttons and macros. If you want to make that type of a game I would learn C++. It is a better language for programing games, and is the industry standard, so its easier to get sample code, or help with a programming problem. Also it would probably take less time to learn C++ and write the game then to just write it in VB. Try to make a Tetris clone if you can. It is nice for a portfolio.