The One With Chandler In A Box - S4-E8
Monica: Fine, judge all you want to, but [to Ross.] married a lesbian, [to Rachel.] left a man at the altar, [to Phoebe.] fell in love with a gay ice dancer, [to Joey.] threw a girl's wooden leg in a fire, [to Chandler.] LIVE IN A BOX!
Answer: The painting doesn't have a name, and if it does it is never mentioned in this episode.