Are the two tables related in any way? If so, it would make more sense to display only the related records using a subform control. Look at the subform examples in the Northwind sample database.
If they're not related, this table you want to display is probably a reference table of some kind. A better technique is to create a Popup form for it (popup forms stay on top of other windows), and have the first form open the popup in its Open event. If desired, you can close it automatically in the Close event, or you can leave it to the user to close it.
If you really prefer to have the table shown within the first form for some reason, I guess you could use an unbound subform in datasheet view. An unbound subform is one in which the Master and Child Link Fields are left empty. Rick Sprague