Movies that are good but hard to watch because of the subject matter:
- Monster -- good movie that did the right thing by glossing over nothing, but I don't even need to see it again
- American History X
- K-19: The Widowmaker -- the scenes of the reactor repair are painful to watch
- Requiem for a Dream
- Lars Von Trier can be difficult to watch, but I'm not sure if he falls under "good but painful" or "bad and painful" because I think his stories can be pretty contrived to the point where he loses me.
Movies that are boring:
- 2001 -- worth seeing once, but I'm NHF films that don't have a point
- Barry Lyndon -- same deal, but not as bad; had a few worthwhile scenes and at least it looked good
- Solaris (the remake. the original was rough at times but overall it worked)
- Pirates 2 and 3
Boring/slow but still good:
- Ozu's movies -- I'm always bored during them but afterwards I look back on them fondly
- honestly, some of Kurosawa's too -- they're all good, but the pacing kills me sometimes
- Star Trek The Motion Picture