Going back to Ben Affleck, I liked Changing Lanes. Though thought it could have been much better with someone else in the Ben Affleck role. I used to try to stay clear of Julia Roberts, but found myself enjoying Erin Brocovich. Something I wouldn't have given a second thought to usually, but my better half wanted to watch it. Talking of which that's how I ended up seeing Bridget Jones' Diary, and Renee Zellwegger made my flesh crawl in that . You can add Richard Gere to the list.
One thing I was wondering, is do you try to avoid a film if the actor/actress is just doing voice over work. I don't particularly care for Billy Crystal in films - but I liked him in Monsters Inc.