Warning: Your Head May Explode!
I am old enough to have seen this in the theater when it first came out. I have never been the same; it has had a huge effect on my life. After years of intense psychoanalysis, all I could come up with as an explanation was this: during my viewing of this film, all of my comedic neurons were firing so frequently, and so powerfully, that my brain simply could not handle the sensory overload of hilarity which had transpired. I could barely get up out of my seat and leave the theater. For weeks afterward, I could not focus on anything. I found myself weakened, enervated, depressed. My immune system had become compromised, and I caught frequent chest colds and coughs. I lost my job, and eventually, my family and friends. I converted to Judaism, and became a recluse. I took to wearing strange disguises and weird costumes in an attempt to blur my identity. For many years I spent my evenings and weekends in a vain attempt to locate a film as funny as Where's Poppa? Despite literally thousands of hours in screening rooms, film societies, obscure movie theaters and festivals, and after journeying through all the stages of home film technology, from Super 8 to VHS to laser disk to DVD, I have given up. No one will ever make a funnier movie than this.

It's so funny I almost wish I'd never seen it, oy, the troubles it's caused!

You know that horror movie Ringu, remade in US as The Ring? They watched a tape and then died. Same idea with that one in the Halloween series--was it 4??--where if you watched the pumpkin your head would explode? That's what this movie is like. Don't be surprised if your head, or maybe your chest, explodes or bursts into flames from the sheer, unadulterated, unmitigated hilarity.

I'll keep this short and sweet...
Without a doubt, one of the funniest movies I have ever seen. I mean, laughing so hard tears come out, funny. It never gets old.

I prefer the "alternate" ending.
This film is a hoot!
If you love very dark comedies this is the movie for you.

It pokes perverse fun at a wide array of things, such as: military officers, lawyers, black muggers, homosexual rape, professional football, Alzheimer's disease, parent-child relationships, and coprophilia.

I've seen this film twice before (once in 1975 and again in 1987). Until now I had never seen the so-called "alternate" ending. It is obvious that this was actually the ORIGINAL ending, i.e. it is simply the last 5 minutes of the film that was trimmed-off to give the story a happier ending.

This alternate/original ending is MUCH darker and perverse than the "shorter" ending, but it is also very poignant which is the reason I prefer it.
If this movie was made today a doubt that a major studio would allow such a dark ending. (Unless the director had a lot of influence/power)

Where's Poppa
If you like dark comedy and extreme satire, you will like this movie. If you like fast paced action movies, this is not the one for you. It moves painfully slow at times. I have been told by a reliable source that the book the movie is based upon is a great read.

Hilarious!
This movie is a classic. Every actor does a great job and the script is hilarious. They don't make movies like this any more.