We've maintained the car well, but sometimes when I come to a stop and either is sitting at a light or when I put the car into park while in a parking lot for example, it seems to run a bit rough in idle as though it wants to choke out.  Not as bad as I really think it will choke out, but it doesn't run as smoothly as I would like, just seems to be running a bit rough, not really any vibration just rough. I try to put the car in neutral or turn off the car if I'm parking in a lot to avoid something going wrong.  There are no codes on my OBDII scanner.  I'm approaching my 60K service where the spark plugs will likely be changed out - do you think it could be a spark plug issue?  Am I just overly concerned or does any of this sound like a reason to take it into a trusty "Scotty-like" shop?

Thanks!