Yeah....the movie stunk.
The acting was fine. The script and pacing were the major problems.
The story had nearly all of the plot points from Johns' Secret Origins. It simply executed them very badly. There are simply too many blasted subplots and character histories intertwined with the director choosing to give the wrong ones precedence over the others.
Going into spoiler territory now:
Example, Hal's training on Oa is only 15 minutes long vs the eternity spent on the romantic subplot with Carol Ferris.
Another one, Hector Hammond's solo buildup to villain is also long, there is a past relationship between Hal, Carol, and Hector and their parents, but that little factoid doesn't come about until well into the film and is only given one throwaway line at a party. That bit would give the fight between Hammond and Hal a large amount of emotional weight to it. Of course, we don't really get an epic fight either. It's a brief scuffle and then the threat they spend a large time building up gets it's soul sucked up by Parallex.
The Parallex fight doesn't pass the smell test either. It was defeated way too easily by our main hero. Who, did I mention, had a whole 15 minutes of training (well, more getting his rear end handed to him by Kilowogg and Sinestro) and Parallex had snuffed out atleast 7-8 of the Corps best Lanterns.
This movie was supposed to be DC's answer to Iron Man. Warner Brother's would have done well to emulate that movie by cutting out a lot of the romance and focusing on building Jordan's character along with some great action sequences. But, no, they went and made something that should have been relegated to the CW as a television pilot.