OSX won't boot, linux works fine.

Hi y'all. Been reading these here forums for advice for quite a while now, but this is my first post so please bear with me =D

So, about a month ago, my macbook was lookin real thirsty so I gave is a good helping of some soft drink. Well it didn't like that too much, and thats where my troubles began.

Needless to say, I immediately removed the battery and turned the thing upside down. Later, I opened it up to clean it out real good and let it dry for a few days.

I booted it up and everything worked perfectly... for a bit. The second time I booted, it took FOREVER, but then everything worked fine. The third time I booted, it took half an hour to get to the login screen, and then froze.
Subsequent boots result (after a LONG time of the fan revving at full speed) in either the folder with the question mark, or a slightly more blunt 'no' sign (like the no smoking sign, but sans cigarette...)

Here's the kicker: though the whole ordeal, I've been able to boot into linux through bootcamp just fine. I can also mount my OSX partition, and the filesystem seems just fine, as does the integrity of all my important files (photos, music, movies, documents). I backed all these up.

Now I wanna get my mac back. Unfortunately, my OSX install disk is in california and I'm in japan. The other day, I finally got my hands on an english-region install DVD from a colleague, only to find out that I lost my superdrive in the accident. *sigh*

So, I'm wondering if anyone here knows how I can just make my mac boot from my seemingly healthy OSX partition. I'm guessing that some boot record or something became corrupted and I just need to restore it. Any ideas?

Thanks!

[edit]
D'oh, I forgot to mention the mac-pertinent things I've tried so far:
single user mode: doesn't work
verbose mode: doesn't work
flashed pram: now I have a chime after power-on, which is actually annoying to me. it wasn't there before...

 

Quite right, not an Air.

I don't have access to an external DVD drive here, unfortunately. Even if I did... it would probably be Japan region-coded. Or does this not matter for the OSX DVD?

Also, I'm just about as interested in a solution to the problem as I am in repairing my laptop. Clobbering the old installation is the easy way out; can anyone figure out why it doesn't work in the first place? As I said, the drive seems to be healthy enough...