I agree with Mushtang that a reboot is a retelling of a story in a different way, while a sequel is a continuation of an original story, even if that continuation is many years later and is meant to revive a story that has been dormant.
I said earlier that I don't really like the lack of imagination shown by endless sequels and reboots, but sometimes the movies really are pretty good. I really liked Jurassic World! That was fun! I also have enjoyed the new Planet of the Apes movies. Personally, I like the new Star Trek movies, although I understand the objections. I'm looking forward to the Star Wars movies too.
I just wish there were more original ideas. That's why I'm REALLY looking forward to The Martian.
Well.... I saw "Terminator Genisys" tonight. I had not even been anticipating it that much, but it was a weird day and at 9:45 I got to wondering... is it playing now and could see it tonight? Yep, a 10:20 showing.
It fits more into the category of sequel since it takes the original movie's 1984 timeline and then..... [spoilers]. Wasn't practical to have the same actors as in the original so those parts were re-cast, such as Sarah Connor being played by the Mother of Dragons. I mean, Emilia Clarke. Though they worked out a way to have Ah-Nuld in it, both current-age and CGI younger 1984 versions. And another actor from the original is in it. A notable actor playing a new role is Matt Smith, who played the 11th Doctor in Doctor Who.
I LIKED IT.
There's some mixture of elements in the first two movies, even though this is a sequel. Also a bit of Back to the Future and even a dash of Blue Thunder. Lots of action, of course, but also a crap-load of story going on with a few "WTF" moments (in the sense of surprises, not crappy), even some funny moments.
As for other movies that get sequels.... it's all about how good each sequel is. To me, Aliens was a better movie, than Alien was. The three Star Wars "Prequels", were very disappointing with effects over plot and silly alien creatures that I had to figure some were created just to show off for the Boss - George Lucas (I do not even mean JarJar, the less said about him the better). Will Episode 7 be more like the original three, or the prequels? Well, looks more like the original three. There was no purpose to make yet another one that would be as crappy as the prequels were.
Remakes, those depend. I LOVED Ben Stiller's the Secret Life of Walter Mitty. And yes I saw the original with Danny Kaye but never really got into it. Of course his is not just a remake since the story is a lot different, just uses the basic premise.
Kristen Wiig was great in that movie (And may be great in The Martian as the NASA PR person, long as she does not get out of control). But I hated about 3/4 of the characters she did on SNL.... annoying (Checkout lady at Target), annoying (Lawrence Welk Show baby-armed terrible singer), annoying (Gilly), and other annoying characters.
So, Melissa McCarthy....she has been good and funny in some stuff, and in some other stuff that wasn't very good. I think in the ones that were not very good..... for the most part it wasn't her but the character and the script..... and the director. I mean, other comedic actresses would not have done better and could have done a lot worse in those same exact movies.
Same could be said for some actors like Jim Carrey and Will Ferrell. They have made some fantastic movies, and some horrible unfunny bombs. "Land of the Lost", I think Ferrell personally pushed to get that movie made, if so then that's all on him, and OMG did that stink. So did "Bewitched" which also had Ferrell as Darren Stevens. While OTOH some other TV inspired movies turned out well, like the Addams Family, and the Brady Bunch movie.
Of course, if there were no movies made of TV shows, we'd have missed a lot of great Star Trek movies with the original cast (usually the even-numbered ones were good) and the Next Generation's "First Contact" movie. The recent two, that imploded Star Trek History, I watched. But for one, I hate how they ruined established history (Canon) in big ways (Vulcan destroyed, unforgiveable), and for also blowing a lot of what made Star Trek so special, going for emphasis on mind-numbing effects over storyline (see also Star Wars Prequels).