If you try to drill-down to an account within a report and you don't get the magnifying glass or are unable to select any of the accounts you may be experiencing a display issue.
To verify this, move Quickbooks onto your main screen and see if you are able to select the accounts. If you are able to select these accounts, then you'll want to adjust your display settings.
If you set one of your external monitor to become the main display
Right Click on desktop > Display Settings > Make this my main display
Quickbooks will function correctly on the external monitors.