Tags in contact reports
If you are talking about eg http://d46.demo.civicrm.org/civicrm/report/instance/2?reset=1 then no there is no option via the UI to do so. A developer would be able to add such a feature I expect.

Meantime there are other options such as: you can use eg Advanced Search, find the contacts you want to export, select "Select fields for export" then in the Export Mapping you can set the Tags field, and it should include that data with all the contacts Tags in a single cell separated by a comma. eg

Irvin Deforest | Volunteer,Major Donor
alidacooper@airmail.biz | Volunteer,Major Donor

You can then save that Export for future use. I have done this on Demo - it is called Contacts and Tabs via "Select fields for export" and then look under "use Saved Mapping fields".

But demo site will flush in a few hours

HTH.