Personally the frat atmosphere alone would keep me from recommending Dartmouth but that’s just me. Google the Rolling Stone article about Dartmouth’s frats. Things might have changed since then but frats remain a significant part of the atmosphere as far as I know. While both schools are woodsy (I use that word rather than isolated because I like the woods), Dartmouth has more incidences of untoward events because of that factor. Yes, Dartmouth offers skiing too, and it’s beloved by many, but D is known for raucous parties plus it developed an atmosphere that led to the recent professor/student scandals. I’m putting this information here so that you can evaluate these things for yourself.
https://www.nytimes.com/2019/08/06/us/dartmouth-sexual-abuse-settlement.html
Williams to my mind hasn’t had these issues. Others may know more than me.
To me the question is, given an equal level of isolation, which school handles it in the manner that you prefer?