I have a lot of confusion regarding lenses!

If anyone could shine some light for me I would really appreciate it.
For starters, I own:
K1000
SMC Pentax-A 1.7 50mm
Hanimex 'automatic' 2.8 135mm
Questions:
1)The Pentax does not say 'auto' or 'automatic' on the front, but yet it has a locking green 'A' setting on the aperture ring. What does this mean? Does it mean that although it is a manual focus lens, it can be automatically metered by a supporting camera body?
2)The Hanimex lens specifically says 'automatic' on the front, but yet there is no 'A' setting on the aperture ring. Does 'automatic' simply mean that the lens is a preset lens and is not one of the old lenses that had to be focused first and THEN manually stopped-down? It doesn't mean that the lens is an AF does it?
3)What exactly DOES 'preset lens' mean?
4)I have been browsing the net for a while in search of an old, cheap, used wide-angle lens. I initially wanted to find a fisheye, but I've discovered that "old, cheap, fisheye" is hard to find. Two lenses I am looking at are an 'Auto Promaster Spectrum 7 MC 1:2.8 28mm kmount" and a 'Coated Super Albinar Auto 1:2.8 28mm k mount." Is one lens superior to the other in terms of quality, or are they comparable? Also, are these lenses 'automatic' in the same sense that my Hanimex is?
Thanks in advance for all help!