I guess I would go with:
Veneta 8/27/1972 (82 is good too)
Portland 5/8/1980 (opened second set with Fire on the Mt and Mt. St. Helens blew...I still remember a bunch of dead heads wandering around in the ash falling and the city being really quiet after the show. Sound is much better on recordings than it was live)
San Diego 8/7/1971 has really good Jerry & Phil synergy
Oakland 2/17/1979 (Kieth and Donna's last show)
Eugene 6/4/1982 My all time favorite has to be a non-dead show...Jerry and John Kahn did a couple of shows at the South Eugene High School Auditorium in June of 1982 and the second show was amazing. At one point they paused for what seemed like a long time and the audience was in a trance, you could have heard a pin drop. Jerry broke it by saying "pretty quiet out there" and people began calling tunes, clapping, etc.