The statement by TardisX that weapons don't work inside the TARDIS control room is completely false. The Doctor surprised the cybermen leader from behind with the gold star (gold is lethal to them) and rubbed it into his suit, causing him to stumble around the control room firing his weapon repeatedly into the TARDIS console. This damaged the console preventing the Doctor from saving Adric.

Furthermore, the answer previous question "Can you fit a TARDIS inside another TARDIS?" is YES. This occured in the episode Logopolis, in which the Master's TARDIS materialized in the same location as the Doctor's TARDIS, and ended up inside it. This made for some very strange scenes where the Doctor and his companions end up going into a TARDIS inside of a TARDIS. There was another strange issue with the TARDIS in this episode, being that it was in fact so large inside that there were areas that the doctor hadn't been to in a very long time, and were literally crumbling from age.