I'm assuming you're using WebView, if that's the case, run the report and hit help to find out details about the different metrics on that report. As for how talk time is generally measured, most of the time it's just the amount of time your agent has been talking on an inbound call, however some metrics include hold time too, e.g. average talk time.
These are the paths to get to each CCX logs through CLI. They may be helpful if you are having issues accessing RTMT or downloading logs through it.
If you want to download them you have to prefix "file get " and you can add one of the options (re...