This also works for the TI-89t, but you could also play with Dialog boxes, too, if you wanted to make it fancier. I don't know what P is since it isn't used in calculations, so I thought it was just an option:
Dialog
Title "Title"
Request "balance",b,0
Request "rate",r
Request "compounds",n
Request "time",t
DropDown "Option:",{"1","2"},p
EndDlog
However, as a warning, B,R,N, and T are strings, so you will need to use expr() on them to convert them to numbers to perform calculations.
You can also make your program into a function if that is easier, but that doesn't prompt for inputs. Still, you could do:
func1(b,r,n,t)
Func
Local b,r,n,t
Return b*(.01r/n)/((1+.01r/n)^(n*t)-1)
EndFunc
Then on the homescreen, you could use it just like a regular function.