93 Regal - Engine Stuck? Water in Oil?

Hi, I posted earlier about a coolant leak I was having with the plastic upper plenum on this vehicle : RE: http://www.automotiveforums.com/t208420.html

Anyways, I replaced the plastic plenum with a new one, and Refilled the coolant system. I checked on it every couple days, as it seemed fine finally. NO External coolant leaks. My girlfriend then drove the car to work, and she said it ran fine on the way. When she was about to get off of work she went outside to warm up the car, (because we were about to get a snowstorm). She said it ran very rough as if it was "surgeing" - she could feel the whole car somewhat shake, as it surged. She figured it was just really cold out, so she continued to run it for another 10 minutes, then shut it off. When she got off work, she went to start it, and it would just crank, but not start. Then she called me. When I got there, I got One good crank out of it, then it seemed the battery had died. (An Optima By the way) -- Is sounded VERY odd, as it cranked over but did not start. We hooked jumper cables upto it, let it charge for a while, etc... Got afew more Little cranks out of it, to thepoint where it would not even BEGIN to crank anymore. The lights are bright, etc. So I KNOW there's enough juice in the battery. I checked the Radiator, and to my astonishment the coolant was WAY LOW... checked the Motor Oil, and it does seem a bit Milky. I am thinking it could have been the head gasket. I ended up towing the car home, as now I wonder what to do...
Does it sound pretty siezed?
What could have possibly broken inside to cause it to seize, the way it did?
Do ya think it would be hard to fix?
Could the starter have gone bad?
Should I just buy a new ENGINE for $475 at my local auto recycler?

Thanks in advance.... This car is really starting to bum me out, after all the money I've put into it over the years. - Jason, CO

I know it's been a while, but I'll chime in anyway.

Hate to say it, but it may very well be a blown head gasket. I had this problem on another vehicle and it was really noticable after it sits. It would start though but it would be rough till it heated up. But the water loss was to great to run it on a regular basis. Typicaly the pressure in the hot cooling system pushes the coolant and water into the engine. Sometimes it's only going into the crank case, sometimes the cylinders, but could be both. The oil gets milky from mixing with the water and coolant while running. That sounds like it's what happened to you I'm afraid.

where the lights bright while cranking? I wouldn't think it's siezed though. It could have just been feeding off the other battery till it sucked to much out of it. It all depends on how long this condition existed and if it's been running hot for a while. I suspect that could be the case.

Replace the head gasket, have the head looked at in a respectable machine shop. Should only be a few hundred dollars if you do the labor.

If you still want to just replace the engine with a used on. Pick one from a car with a damaged body. Better chance of getting a good one.