Two of my favorite under-rated movies...Being There and Love and Death. Both are well worth catching if you ever get the opportunity.
Being There, staring Peter Sellers. I think this was his last major film. The film manages to be both very funny and profound at the same time.
Love and Death starring Woody Allen. Nothing profound about this...just tons and tons and tons of classic Woody Allen, back in the day when he was funny (as opposed to the "serious" actor and director he became later).