I love Kristin and have watched her in other interviews where she has been fabulous. I agree with the comments that this particular one didn't go too well for whatever reason. There is no chemistry between Kristin and Ellen for whatever reason (Ellen was kind of disengaged; she doesn't seem to take to the whole "I am a silly blonde" persona as well as Letterman does).
I also agree that the whole segment seemed very plastic. The whole first part was, "I am going to tell this long and non-spontaneous story about my hair," the opera lesson was schticky and silly (if she ever decides to give a master class, I hope she is a better teacher than that), and I thought even the John Spencer part didn't come off that well. I mean, the guy died about 2 weeks ago, and Kristin didn't seem like she was still upset about it (to me, the whole recollection of him came off as very rehearsed, like the "Jolly Rancher" thing). I think Kristin needs someone more like Letterman who will throw her off her guard more so that she doesn't just do her rehearsed routine.
I also don't understand why she doesn't sing during her appearances -- most of the audience doesn't know she can, and most of them would really be wowed by her talent. I don't see how it would hurt her -- it hasn't hurt Catherine Zeta-Jones or Hugh Jackman to let people know they have musical talent.
"What was the name of that cheese that I like?"
"you can't run away forever...but there's nothing wrong with getting a good head start"
"well I hope and I pray, that maybe someday, you'll walk in the room with my heart"