I've played with 64-bit client for a while, but it would crash like every 2 hours for no reason. Switched back to 32-bit client, haven't had a crash ever since.
I am surprised by how rushed 3.0.0 felt. And how slow the developers are at fixing major bugs. All/ally chat is still bugged, for example.
You don't have to be good at a game to enjoy it. I mean, I've spent something like a total of 3,000 hours on Starcraft 2, so, at the very least, my instincts, my muscle memory is extremely refined and I do most of the things without thinking - but even when I was playing the first time, not knowing a thing, I still enjoyed the challenge of learning everything new and making do with what I already know. Ladder might be quite frustrating though, but you don't have to play ladder to enjoy the game (I haven't played ladder much since HotS came out - Arcade is where it is at for me, plus campaigns).
Try popular maps like Squadron TD, Desert Strike HotS, Nexus Wars... These maps don't require any micro or macro. You still have to invest a lot of time in them to get good at them, but you can start playing right away without getting demolished by stronger players. If you want to practice for ladder in a non-pressure environment, play 4v4 Monobattles - this is how I learned to macro.