A full length feature script usually runs anywhere between 90-144 pages. Keep in mind that horror scripts tend to be shorter than most other genres. I would say even an 86 page horror script would be acceptable.
Dialogue is tough at first. What helps me is just think about real life situations. Think about when you talk to your buddies or your family. Heh, it helps me.
Well, Meh, you write for this site... and very well might I add.
Filmmaking For Teens is a book that I highly recommend. I got it as a Christmas present and read it in a couple of hours. The Screenwriters Bible is another good one.
hey i just finished my script thanks for all u guys did the advice and shit liek that it really got me to focus on it more its 76 pages right now but theres sumthings that i wanna add to it that i thought of so by the time its all finished i believe ill have at least 80 to 85 cuz theres alot more that i need to fix and shit liek that so ill tell u how it goes later