1. ____ Actors at Old Tucson were good.
2. We enjoyed _____ very much
1 is much more interesting, because both possibilities are perfectly OK (although "actors" should be in lowercase"). There's very little difference in meaning between the two possibilities, too. I think I would be inclined to say "those" when speaking to someone who had seen the play with me, or "the" otherwise.
Looking for ESL work?: Try our EFL / TOEFL / ESL Jobs Section!
Both would be OK, but using those would perhaps imply that they were better than some other cast (or group) of actors.
People are waiting to help.