If we select 1 st option ,then it should show result of last week(Sunday - Saturday).
And if we select 2 option , we should result of current week (Sunday - current day) only.
You can go with a drop down option in your dashboard. Please refer the below question and its answers.
https://answers.splunk.com/answers/242704/how-can-i-create-a-drop-down-for-panels-in-a-dashb.html