Multiple Totals metrics can be selected at one, and they will be shown side-by-side in the report, listed by date.
Segmented metrics must be individually selected since they create a table of values by date.
There are daily totals (day period) available, as well as running 7-day totals (week period) and running 28-day totals (days_28 period). Some metrics are only available as lifetime totals. Selecting a period of all will get you all available periods for the metrics selected.