I have a Radio Shack PRO-91 would that work for Aurora Police and Fire??
No. It's an antique that tracks analog Motorola systems and the only analog Motorola system left in the area is United Airlines at Denver International Airport.
Though some of these are distant you should hear the following conventional frequencies in the Aurora area with that radio.
151.085 CDOT Eisenhour Tunnel
151.115 Douglas County Fire Dispatch Simulcast
151.355 Boulder County Fire RED-1 Dispatch
151.430 Intercanyon Fire
153.785 Weld Fire Paging South
153.845 Gilpin Fire
153.875 North Fork Fire
154.070 Denver Fire station alert and Dispatch simulcast
154.280 FERN
154.370 Boulder County Fire RED-6
154.415 Boulder County Fire RED-3
154.725 Fairmount Fire Simulcast
154.860 Gilpin County Law
154.905 CSP State 3 VHF
155.220 Elk Creek Fire
155.475 National Law
155.610 Clear Creek County Law
155.655 Boulder County Law Yellow
155.835 Golden Fire Simulcast
159.270 Boulder County Law Green
453.475 Evergreen Fire 2
453.900 Federal Height Fire Paging
453.950 Evergreen Fire 1
460.375 S. Adams Fire Paging
460.425 CLEER
460.525 Brighton Fire Paging
460.550 North Metro Fire Paging
460.575 S.W. Adams Fire Paging
464.775 Aurora Schools Bus ops
464.875 Aurora Schools Security
853.7875 STAC-D