"Total" is the number of events including duplicates, "Unique" is the number without duplicates.

The first row gives the total for all dimensions, all further rows give the number per dimension (i.e. this is broken down by the alphanumeric "label" in the first column). So basically they are all correct, they just show different things.

The weird thing in your screenshot is that the totals in the first row are smaller than the totals per dimension. I cannot explain that, this should be not possible.