1) Find out from your urologist where on the "Bosniak Chart" your cyst is. It's a chart that ranges from 1-4 and let's you know the relative severity of your cyst load/case.
2) Many people go their entire life with a renal cust and never know they even have it.
3) If your urologist offers it as an option, renal cyst-decortication is an option.
4) Don't sweat the 2mm stone. It may decide to stay put for the rest of your life, or it may decide to come down. If it comes down, prepare for the worst pain you've ever felt.
Have your urologists number handy, and if the stone starts to pass, call him/her and let him/her know that you're passing a stone. If it's too much to bare, head to the ER and they'll take care of you. Stones are painful, but as far as I'm aware, a 2mm stone won't kill you (it'll just hurt like a ba$tard).
Good luck to you.