It is hard, but I thought it would be valuable to pursue this and create a guide for jazz newbies.
Yeah, I personally listen to Sketches over Kind of Blue 5 to 1, but KOB is widely considered Mile's best. For Ella, I'd pick "Clap Hands", for Bill Evans (although Gil has his spot among the greats) it'd be "Debby"- although Conversations w/ Myself might be my personal favorite-hard to pick.
So, if you had to choose one, and only one. which would it be?
If we get enough response, I'll compile the results.