If you're only going for one Alpine Valley show, I'd suggest this one. But why choose? This is why Al Gore invented external hard drives, right?

Sunday, 06/21/2009
Set 1: Brother, Wolfman'sWolfman's Brother, Funky Bitch > DividedDivided Sky, Joy, BOTTBack on the Train, Taste, Poor Heart, HorseThe Horse > SilentSilent in the Morning, TMWSIYThe Man Who Stepped Into Yesterday > Avenu Malkenu > TMWSIYThe Man Who Stepped Into Yesterday, TTETime Turns Elastic
Set 2: C&PCrosseyed and Painless[1] -> DwDDown with Disease[2] > Bug > Piper[3] > Velvet SeaWading in the Velvet Sea, Boogie OnBoogie On Reggae Woman, SlaveSlave to the Traffic Light
Encore: Grind, Frankenstein[4]
[1] Brief Let It Grow (Grateful Dead) tease.
[2] Taste tease from Trey; unfinished.
[3] Brief Can't You Hear Me Knocking tease.
[4] Page on the keytar and Trey on a five-neck guitar.
Performers: Trey Anastasio, Page McConnell, Jon Fishman, Mike Gordon
Notes: During Brother, each of the band members’ children jumped into a bathtub placed at the side of the stage. Afterwards, Trey introduced them and wished everyone a happy Fathers’ Day. Funky Bitch was played in acknowledgement of a fan who had been holding up a sign requesting the song at this show and the previous one. Crosseyed and Painless included a brief, subtle tease from Page of the Grateful Dead’s Let It Grow. Trey teased Taste near the end of Disease, which was unfinished. Piper contained a brief Can’t You Hear Me Knocking tease. Frankenstein featured Page on the keytar and Trey on a five-neck guitar.
This show was part of the "2009 Early Summer Tour."