|"Is it possible to build a gaming PC using a micro ATX case/mobo etc"|
Of course it is. However, the width of the case generally doesn't change much, just the height & possibly the depth.
"is there a particular mobo and graphics card you recommend?"
Can't recommend a board without knowing which CPU you wanna use & how much you're willing to spend. We'd need a budget for a graphics card as well. The Tom's Hardware "best graphics" series hasn't been updated in a while but hopefully this article is helpful: