For me it's most likely Falling For You. It is responsible for my favourite "Post-Pink" live performance and the 1996 Philly performance of it is one of my all-time favourite Weezer videos.
I love the passion in Rivers' body language and voice in the first video and the total command of the axe he displays in the second video. Both videos give me the best kind of chills.
OID, Extended Midget Tour, Kalamazoo, Michigan, 12/4/2001
I get the same chills watching these videos over again, too... the Chicago shows were beyond incredible.... I was so spoiled to hear OiD and Falling for You twice in two nights.... and then to hear Butterfly for the first time... wow... life-changing stuff, people...