You can't technically add a recordset to a combobox, but if you have the name of the recordset (the table?) then you can put the name of the table inside the combobox. When the user selects it you will need to run a query to load that recordset up based on the name in the combobox.
Try using a data combo box. Set the recordsource property = to the recordset name. Set the listfield property = to the recordset field you want to populate the recordset with.