MacBook died during system update

Hi all, first time poster here. While my MacBook was updating, it ran out of battery power. When I plugged it into my charger and turned it on, the grey screen came up with the apple symbol and the loading circle thing. Any ideas on what to do? Thanks in advance!

It's been two hours since it started to do this, by the way.

You're usually given a warning when doing updates that the machine should be plugged into AC power not on battery. Did you miss the warning?

Let the machine fully charge, and then reset the PRAM. Afterward, try booting again. Let us know.

I did see the warning, for some stupid reason I thought I could beat the system... I tried the PRAM procedure, but it seems to have reverted back to how it was before trying PRAM

Since the machine quit in the middle of an update, there is more than likely damage to OSX depending on which files were being written when the update got interrupted.

Do you have your OSX DVD that came with your machine? What version of OSX is on your Mac?

I unfortunately don't have my disk, I'm at college and it's back home. I'm using Lion, which I installed through the App Store (if that makes any difference).

can you restart and hold command + R to get into restore mode and then reinstall lion?

I restored it, but it's taking an unnervingly long time to verify my computers eligibility with Apple.. Will this mean I lose everything in my computer?

EDIT: it's still trying to verify my eligibility... Any reason this would be taking so long?

I gave up on trying to restore it, it's still "Loading Installation Information"..
Any other suggestions?

I don't know, you may have to call apple care? I have googled it and can't find anything like what you're experiencing.
Did you try opening in safe mode? Shut down and then restart and hold the shift key. I don't know what that can do, but it may at least get you back into the computer. You may be able to start the upgrade again from there?

Thanks, I'll try that!

The shift key should be pressed as soon as possible after the start-up tone, but not before it.

I tried it and waited a few minutes, but I still got the normal grey screen :l

Okay, you are supposed to release the shift key when the spinning gear appears on the grey screen. I didn't mention that before, sorry.

After that, I am not sure what to do. I am researching other start up options....

Still didn't work... May have to hit the genius bar tomorrow

they would know more than I....

I didn't find much else except this page:

Mac OS X: Gray screen appears during startup you could try that.... most of which you have already done I am assuming. sorry I couldn't help more, good luck

Golden rule... Never update on battery power!!!!