Kyle, with normal speed films the 1/250 will probably be all you need....( unless that subject is about to leave ,LOL )

The speed comes into play with slow films for instance... I used nothing but Kodachrome 2 for many years... my Nikon has never had anything different in it.. for 2000 plus pictures...

It (K2) used to have an ASA of 25.... so I had to use longer amounts of time to get enough light .....

The trick is that at about 1/30 second you have a problem holding the camera still enough....for sure anything longer than that you want a tripod or be braced against something.. ( or use the timer button and set the camera on something )

Other than that... what changes is still the depth of field when you change from one F stop to another.... assuming you have the film speed to compensate for the combos....