Smoky exhaust

[SherwoodForest]

Greetings from a first-time poster. Just had to come here to make sure I'm doing the right thing. My 00 base Boxster wouldn't start for a couple of weeks while it sat in the garage. Lights, radio, windows all functioned (though the window drop-down function is totally screwed up). The car turned over, but not enough to start (even though I had it on a battery maintainer for the whole two weeks). So I finally got around to calling a Euro car repair shop (40 minute drive) and they advised a jump start attempt before having it flat bedded to the shop. So we jump started it last night. The startup sounded a bit funny for a couple of seconds (like something loose floating around, maybe) but after cranking it for a full minute or so, the car finally started and ran and seemed to settle into a slightly oscillating idle. Unfortunately, grey smoke poured from the exhaust. Too long to be normal, and it was constant, so I shut it off after a minute or so and restarted. Same result. Constant grey smoke. So I let it sit overnight and started it again this morning. Same grey smoke! Hmmm ... could this be the dreaded air oil separater thing I've heard about or something else? And I assume towing (expensive!) is preferable to the risk of driving. Advice? Thoughts? Arrgghhh!!!