I would just buy some pretty plastic ornaments ... and NO TINSEL, as it can get lodged in their stomach and be deadly! Lights should be fine too ... just watch to be sure that Mina isn't chewing on the cord or bulbs! If you think she will, then maybe just get a color light wheel or something.

Be prepared for Mina to climb the tree, it WILL happen .... a good idea is to tie it with thin cord to a nail on the wall or something else, just to make it a little harder to tip over!

Other than that, just have fun decorating .... but don't buy anything so precious that you wouldn't want it ummmmm, broken!