It looks like Ivan Reitman does mostly light throwaway comedies. Casting Schwarzenegger in the lead role three times makes it obvious he doesn’t take his movies too seriously. Looking at the list of movies I haven’t seen yet, I really have zero desire to see any of them.
Kindergarten Cop: Schwarzenegger is a cop who has to pretend to be a kindergarten teacher to find a drug dealer. The lame premise mostly leads to a lot of unintentional comedy as Arnold tries to be funny. A few laughs, and it’s eminently watchable, but far from good.
Grade: D+
Twins: There’s surprising chemistry between Schwarzenegger and Devito beyond the lame premise that these two are fraternal twins. Like the previous movie, some laughs, but nothing all that memorable.
Grade: C-
Ghostbusters: I can’t say I like this as much as most people, but it definitely has cultural significance and great nostalgia in addition to great acting. The scenes themselves are as inconsistent as any other Reitman movie, but the casting was perfect and these guys play off each other so well. But there’s only a few laughs in there for me.
Grade: C+
Dave: If you care at all about political accuracy this movie could easily annoy you as the satire that’s attempted is childish. However, Kevin Kline is great as a fish-out-of-water who must pretend to be the President while the real chief is in a coma. He’s a dead ringer for the real guy, but lo and behold he’s a lot more friendly and goofy than the guy he replaced. Perhaps the best part is that the first lady (Sigourney Weaver) is also not let it on that her husband has been replaced. Very likable cast.
Grade: B
Other Ivan Reitman Films You May Have Seen
No Strings Attached
My Super Ex-Girlfriend
Evolution
Six Days Seven Nights
Father’s Day
Junior
Ghostbusters II
Legal Eagles
Stripes
Meatballs
Death By Troggles 
Ghost Busters (yes, the actual title has two words, and this bugs me to no end because it looks so wrong) is one of my favorite comedies. Top five, I’m sure.
Stripes is fine enough. Meatballs was a ton of fun in my youth, but I have no idea how that would translate.
Evolution, though…I almost suggest seeing it just to appreciate what it looks like when a director rips himself off. This movie had so many elements, so many jokes and characters lifted straight from Ghost Busters (except they were all of lesser quality) that I was livid until I reached the ending credits and noticed it was the same filmmaker. Then I got intensely sad for the poor guy.