How to create a report showing a subset of contacts and their tags
Follow the below step get the contacts report with tag values.


Find contact using search option. (sitename/civicrm/contact/search?reset=1)
Click on search without apply any filter if you want report for all contact.
Select the contacts and then perform the action export contacts 
select this option Select fields for export and Do not merge on this page.
Now on this page you select the fields that you want in your report.


That's all.