iDVD and DVD disc drive problems

i am so frustrated with these issues. i have tried everything that any forum suggested. the issue is iDVD used to work up until the disc was in the middle of burning then the whole computer would freeze every time. then i didnt use iDVD for MONTHS and now when i try to use it, i click on the dock icon and the icon bounces once or twice and then the error message pops up that says "the application idvd quit unexpectedly" without even opening the program. i have tried deleting the theme files...and reinstalling idvd from the osx disc. i have tried getting ilife 09 and installing everything. i have tried repairing permissions. im not smart enough to think of anything else on my own that would fix it. so if you have ideas, please go step by step for me...im no mac whiz.
the other issue, which may or may not be unrelated. the disc drive RANDOMLY decides it doesnt like DVDs. it spits out whatever i put in the slot 10 or more times. SOMETIMES i can get it to work after a long while of shoving it back in over and over. but sometimes it just wont read it. it tries, i can hear it and i can see a red light inside the drive for a few seconds, but then it spits it out. the drive cant be shot, because once it does start working, i can watch an entire movie in it.
please, can anyone help? its driving me nuts!

this is a macbook pro...that i got for christmas of 07 so no, i can not take it in to an apple store (i actually did once for the previous issues with iDVD and i was able to burn 2 dvds before it messed up again)

Did you run a Disk Verify when you checked permissions? And did you use Disk Utility from your install discs?
I would definitely do that again first.
With regard to it spitting out DVD's, it could be the drive. Does it do the same with CD's? It could just be the discs. I had some that none of my Macs would read, but the external burner I had was fine with them.

ive done all that before and tried it again. nothing has changed. thanks for your input though. sometimes the install discs dont even want to work in the drive. its NOT the discs because the other day, i tried for 10 minutes to get it to read a normal dvd. finally it did and i watched the movie in it. then i tried putting it in again and it never read it. it does the same thing with the install discs. only i am persistent because i KNOW they will eventually work.

thanks for responding, this has GOT to be some unique problem cuz i cant find the solution ANYWHERE!

Ok. I think it's your drive then.
Let's try this though. Try playing a DVD in another program, say VLC player for instance.
This will possibly give us some more clues as to what the problem is.
Also, try cleaning your drive with a disc cleaner.
Your next option may be to try an external drive (if you have access to one) and see if the discs are ok in that.