For target shooting and home defense, I'd recommend a longer barrel, such as a 6" version. It makes really accurate shooting easier, and thus more FUN!

The bigger and heavier the gun, the less felt recoil you'll have. Again, more fun. Thus, a Model 27 would be wonderful, but more expensive, than the smaller, more common models.

If you are looking for a fine used S&W, the Model 28 joins its fancier brother, the Model 27 as great choices too!

In the mid-sized frame guns, the Model 686 (new or lightly used) also will be fun and very accurate!

I hope this helps, and best wishes,

Tom