Could anyone tell me with reasonable certainty whether the bright "thing" with the halo around it is actually the sun or if it is a lens flare?
It's both. The sun creating a large lens flare around itself and two more flares at lower right.
For any lunar surface photo you want to know about, always go to the Apollo Lunar Surface Journal
http://www.hq.nasa.gov/office/pao/History/alsj/frame.htmlclick on the mission, then Image Library, and look up the descriptions surrounding that particular photo (AS14-66-9306). If it's part of a pan (often indicated by "right of..." or similar), read the captions from the start to end of the pan, and also go back to Assembled Panoramas with the starting frame's number and see what those captions say, which in this case is...
114:57:20 LM 12 O'clock Pan (289k)
Al took this pan from a position west of the LM. The frames are AS14-66-9294 to 9316. Assembly by Dave Byrne.
A high-resolution version of the eastern portion (9 Mb) and a presentation of anagylphs in context (15 Mb) have been assembled by Eric Jones.
A high-resolution version of the western portion (8 Mb) and a presentation of anagylphs in context (12 Mb) have been assembled by Eric Jones.
Mike Constantine has created a continuous version (1.0Mb) in QuickTime format.
David Harland has used AS14-66-9305 and 9306 to show the LM with Cone Ridge just to the left of the spacecraft ( 0.9 Mb).
...but it includes links to everything. The first link (289k) is to a rather crappy old early-days version of the pan and the later ones are better.
Also click on the Ground Elapsed Time link (114:57:20) and read the journal well before and after that time in case there's more useful info.
Lens flares are so common that they're not mentioned much.
The individual shots in that pan close to the LM are good examples of some of the flares in lunar surface photos, but not all of them. There's a rarer one (in AS12-49-7278) that looks like one end of a single slat from a venetian blind.
That photo got dear old Ralph Rene going in his magnum dopus
Nasa Mooned America! where he claimed that Pete Conrad was not carrying a camera. He missed the fact that the camera was on Pete's chest instead of up at eye level, where it would be of no use.
Ralph Rene was quite hopeless at analysing photographs.
He and I corresponded a little after
Nexus magazine printed some of his hoax claims, and he sent me a free copy of his book.
Nexus didn't publish my rebuttals, but I guess that when there's money to be made from publishing nonsense...
The Apollo 14 12 O'clock Pan also has two good examples of the "blue comet flare" in AS14-66-9292 and AS14-66-9301. It's not a flare that I recall seeing in my photography career and some people have claimed that it must be caused by cosmic rays, but I think JayUtah knows more about it being a processing fault.
There are tiny blue spots in many of the colour lunar surface photos and the earliest I've seen is in AS11-40-5906 at the far right edge, just above the horizon. There are also white dots in AS17-145-22158.
By the way, the quickest way to see the high-res photos without captions is to keep the following link and just change the mission number (twice), and film and frame numbers, and delete the HR if smaller photos are good enough.
http://www.hq.nasa.gov/alsj/a11/AS11-40-5906HR.jpgcan become, with the appropriate changes,
http://www.hq.nasa.gov/alsj/a14/AS14-66-9306HR.jpgNote the extra distorted images of the fiducials/reticules/reticles/crosshairs in the big flare. They have also got HBs calling "hoax" for no good reason. It's just a trick of the light.