1997 Mazda 626 smoking, oil burning and airplane noise

This mazda has been burning oil- goes down 1 quart every 300-350 miles. It puts white smoke out the tailpipe that stinks on start up but thats the only time.
It doesn't appear to be leaking oil, I've never seen any puddles under the car.
It has a loud noise when driving - it sounds like you're riding in a 2-man airplane. It does not change with acceleration neccessarily but does get louder with increased speed and softer with decreased speed.
Not sure if the two are related.
I has recently been running rough when sitting at stop light and when in park. I thought it might be the fuel filter, but my husband pulled it off and it was fine. They were messing with the mass air flow sensor today and when they had it detached, it was running similar to the way it has. The engine light however, has never come on.
The smoking and oil consumption has been going on for about 10 mo and the rough idle has been getting worse since 1 mo. The loud noise has been getting louder for about 8 mo. It has driven smoothly this whole time until this idle thing started 1 mo ago.
I have heard that white smoke possibly means cracked head and that the airplane noise could possibly be wheel bearings.
any ideas?