(setq org-tag-alist '((:startgroup . nil)
                      ("@work" . ?w) ("@home" . ?h)
                      ("@tennisclub" . ?t)
                      (:endgroup . nil)
                      ("laptop" . ?l) ("pc" . ?p)))

Now when I add a tag the entire frame is split up in two windows both of them showing the *Org tags* buffer.  Is it possible to disable this?

There are no problems when I don't set org-tag-alist. 

Many thanks for considering my request.

Petey