1. I go swimming / I have gone swimming - the general activity of swimming
I am swimming / I have been swimming - the precise action of swimming
2. Present perfect cont. is the better tense for the answer to your question, especially if you are still waiting. I would not consider that duration e.g. of the waiting refers to the result, but rather gives more information about the activity. The emphasis is still on the activity.
If you decide to stop waiting now, then you could say e.g. "I have waited too long - I am going home now." It's a result in the sense that it continued to the present (but no further).