Also, you might try concatenating the form reference in so that the explicit value is being passed instead of requiring it to evaluate the form reference itself.
currentdb.OpenRecordset("select * from tbl_list_281_types where [281ID] = " & [Forms]![frm_create_instructor]![Combo1])
I can't be of much help here without understanding your business logic, but besides that this isn't the right section for this question. I've a quick look and I can see that you have no relationships setup.
If you require advice regarding your tables and their relationships you can post a thread in the Tables section of the forum and explain what each table is for + your business logic.
Sometimes I ask posters to post there but there doesn't seem to be much activity there. Perhaps if we start telling them to go there there will more activity.