Grouped exposed filters just don't work on tags
Delete all your existing filters. I think you have misunderstood how they work.

Then add a single filter on the term reference field (field_tags?), expose to visitors, reduce duplicates, and make sure the filter is NOT required. Do not check anything else!

Submit, save your view, and you should have an exposed filter with the options '-Any-', 'Phpto' and 'Video'.

EDIT:

After much discussion, step by step:


Go to /admin/structure/taxonomy and set up a vocabulary calling it whatever you wish (lets say 'media'). Then add terms to the vocabulary like 'Photo', 'Video' etc. If you have already done this, skip to step 2.
In your content type, go to 'Manage fields' and add a term reference field to the type (lets call it 'Media') using the media vocabulary.
Go to /admin/modules and disable Better Exposed Filters.
Edit your view and delete all the current filters in the view. Save the view.
Now add a filter on the taxonomy reference field (eg field_media). Click Add and configure fiter, on the first modal select 'Dropdown' and click 'Apply and Continue'.
On the next modal, check 'Expose this filter to visitors, to allow them to change it'. The 'Filter type' should be 'Single filter'. Make sure 'Required' is not checked. Leave the operator as 'Is one of'. The only other box you should select is 'Reduce duplicates. Now click 'Apply' and save your view.


You will now see a dropdown list with all the terms in the vocabulary you created, plus the option -Any- at the top.