Corrected entry: Whenever Hal is wearing his mask when he is a Green Lantern, his eyes are light blue. But right at the end of the movie, before Carol asks him to remove the mask, his eyes are a darker colour.
Corrected entry: When Hal is getting beat up by the three guys who lost their jobs, it's consistently shown that three men are fighting him. When he hits them with the Green Lantern "fist", four men are shown crashing into various objects.
Correction: Actually they show the same guy hitting the front of the pick-up truck and bouncing off it (from one angle) then into the rear of the truck (from a different angle).
Corrected entry: When Hal's friend comes to pick him up at alien crash site, when he gets out of the jeep and starts talking to Hal his tooth turns blue. (00:22:05)
Correction: That is because there is a blue light illuminating the area, his tooth is just reflecting the light back.
Corrected entry: When greeted by Tomar-Re on Oa Hal Jordan knows all about Tomar-Re's sector. He now knows the number of galaxies in it and number of inhabitants, because his ring has fed the information to him from its database. Yet, it doesn't make sense the ring's database doesn't seem to have any information about Oa, the green lantern corps or the guardians, and Hal has to ask Tomar-Re.
Correction: It's reasonable to assume that the Green Lantern initiation process specifies that the basic information should be supplied by another member of the Corps, and that only subsequent information can be downloaded straight from the power ring. After all, Hal finds it bizarre enough to suddenly know the information about Tomar-Re's sector - had the ring simply info-dumped the whole thing into his head right from the start, he could have completely freaked out, which could lead to him rejecting the ring entirely. A far more reasonable approach to start with a one-to-one chat, then let the ring do its thing after that.
Correction: Hal Jordan's eyes change color for protection of his identity. He can make the mask appear/disappear, but because the girl knew he was 'the green lantern' the eyes didn't change too.