Walls and Ceilings - Is this wall load bearing?

We are hoping to enlarge the entryway between our foyer and living room and after cutting a few holes in the wall to see the guts, I am now wondering if it is loading bearing. The ceiling joists run parallel to the wall so I thought is would be non-bearing, but after cutting the holes I found there was a large beam the went across the archway, which looked like a support beam, two 2x10s nailed together. But now I am biginning to question if it is a support beam or not, as it is sitting on a 2x4 that also stretches across the entryway and that 2x4 is only resting on one stud on either side of the doorway (see bottom of pics 3 and 4), which would be nowhere near enough support. Also, the 2x10 isn't even touching the above 2x4 ceiling plate, which I would assume it would if it was loading bearing (see pic 4). Our house is 43 years old and maybe back then they use these big beam for other reasons. I should also mentioned the foyer has a lower ceiling and comes to about halfway above the entryway.

Anyone have any idea on whether this wall is loading bearing and what the beam is for?

Click on the below link to see the pictures:
http://www.box.net/shared/ifajons8oo

Thanks in advance.

What you have pictured is a header for the opening. It is bearing the weight across the doorway to keep it all from sagging. It is supported on either side of the doorway by two jack studs and a king stud next to them. What are your plans? Having a floor above may not allow for much modification. In fact, it would probably be best to call in a structural engineer to see what is feasible and what isn't.

My hope is to widen the entryway by 2 feet on the right side. Could I not just brace the ceiling with braces, take out the studs on the right and the header, then add a longer 2x10header with new support studs?

Absolutely. That is the way to go, but I would not skimp on building the header. Use the same dimensions for width and construction as the one that is there. And, of course, you will need to build a new one, and not try to lengthen the one you have, right? Go for it and let us know how it goes, and post pix.

Yes, I am going to build a brand new one with the exact same width and height measurement, but to the new length needed. Will let you know how I make out.