You should go to a range that rents guns ...see what they have....and see what fits your hands and evaluate the trigger pulls both in double action and single action.
In general - you're going to see a lot of S&W's and Rugers...there is a difference in the triggers / and you need to hold and dry fire probably 5 or 6 of each to really see what you like or don't like. To me, there is a big difference in the quality of the S&W triggers over Ruger ...but what matters is what you think.
S&W in general...
J frames ...are the smaller guns ( mod 36's, 38's, 649's, etc usually .38 spl ).
K frames ...are mid sized...and a lot more options there. Mod 19's, 66's, etc..and that's where you'll find a lot more .357 mags / and you can shoot .38 spl in them of course. Still comfortable for carry.
L frames ...mod 686 ...a little bigger..
N frames ...mod 27, 28's, etc...Large frame / nice guns - but probably too big too carry / I wouldn't want one Inside Waist band ...but they're ok in a scabbard holster. Way too big for pocket carry...
but you should look at all 4 frame sizes....evaluate the triggers / and do the same thing on the Ruger options...then you can make an educated choice.
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as an example....I find the J frames too small for my hands to be effective - I can't shoot them well at all / in the K frames - a 2 1/2" barrel model 66 ...is a good carry option - easy to carry inside waist band. Good solid guns - decent range gun - good carry gun / L frames mod 686 ...just a little heavier / N frames mod 27's are my all time favorite .357 mag and in a 4" its a great gun - but honestly too big to carry IWB. If I'm just having some range fun ...drawing from a holster....a K or L or N frame in a 4" is a lot of fun ...for tactical drills or whatever. If I go to a 6" barrel, it will still fit holsters I have...but I really have to drag them up and out of the holster a long ways ( doesn't seem like much ) but the extra 2" is a different move to raise my elbow and shoulder that high. I like the 6" as a range target gun ...not a tactical gun / but I like carrying a 6" in the woods ..../ 8 3/8" barrels on some S&W's -- drawing them, is like drawing a carbine...makes no sense....but in a mod 29, .44 mag, they're fun to shoot too.
So you have to figure out how you fit in all those dynamics of weight, barrel length, etc....and find a gun you like.