I hope to shed some light on this for you.
Firstly, regarding the latency or delay, there is little you can do to avoid this.
This is due to thje digital processing of the data (sound and video) over the DSL network, satelights, etc.
You will notice that when you see a news report of a foreign correspondent being asked a question, there is still a delay, as the reciver is still listening to the question being asked after it has been asked. That doers make sense, if you read it slowly.
Anyway, to help a little, the skype idea is not too bad, particularly if your DSL connection is good, and your computer has a little 'grunt' and is not ten years old.
However, one imp[rovement is the microphone, that will make all the difference.
The best one to use (and no, I do not sell microphones) is the Audio technica USB 2020, as it hs a large diaphragm, and is available as a USB mic that plugs directly into your computer, and will massively improve the sound qulity of the pianio over the internet.
Ihave searched the net, and they are available from http://www.hostingsuccess.com/audiocreation
Again, I am not a retailer, but have found that this website explains the use of audio recording on your computer very well.
I have found that skype is also getting much better and more clear, and responsive in transmitting the sound and video with little or no drop out, as long as you have a good laptop and internet connection.
I would be interested if you can lert me know if you have a much better success rate taking this action. I have certainly seen a massive improvement when working this way.