battery burst, line on screen, no won't start up now

The battery on my my MBPro (3 yrs old) burst out of its titanium casing recently. For months prior to that, a thin vertical line ran down the screen, but machine worked ok. Just prior to battery bursting, the MBPro was behaving VERY strangely, likely due to sick battery? The battery is out of the machine now, but the machine won't start up when plugged in. At the very least I want to get my data off the HD. Wondering if its worth hauling it back to the U.S. (I live in Japan) to take it to an Apple Store for a check. Any suggestions on any of the above?

The swelling was probably stressing something causing the vertical line, maybe.

Very likely due to the battery, yes.

I've seen that before, where a bad battery will stuff something in the power controller and they don't run off the power. With the Power out, completely unplugged, press and hold the Power Button for 6 seconds, then plug it back in and see if it powers up.

If that doesn't work I'd say it stuffed the logic board, so you might as well take to it with a screwdriver and pull the HDrive. Look around on the net to find a pull apart for your model.