I would generally agree with RSS, but I think it does depend also on what your long-term goals in architecture are (and to some extent to which graduate school(s) you will be applying). If you want to go into design, then definitely art/art history/architectural history. If you intend to pursue other facets of architecture, other avenues might serve you better. I see that the program you will attend provides a non-accredited B.S.Arch. degree; given that, you should certainly be able to design your own minor, as you stated above, rather than follow a pre-determined minor, in order to flush out your undergraduate degree as fully as possible.