Favorite single issues that I own...(in no order)
New X-Men 114; Grant kicks off his view of the X-Men with a bang. Stunning. I was hooked.
Legion of Super-Heroes (v4) 4, 5; the death of Mon-El and the birth of the stunning Mordruverse. Ferro Lad's a hero in any universe.
Giant Size X-Men 1; the start of the Modern Age of Comics.
Authority (v1) 14; love Quitely's visual take on the Avengers.
JLA 1; Morrison and the JLA--a great moment for classic Super Hero Americana.
Iron Man 128; My name is Tony Stark, and I am an alcoholic.
Doom Patrol (v2) 19; Crawling from the Wreckage indeed.
Fantastic Four Heroes Reborn (1996) 1; love Jim Lee's visual take on the World's Greatest Comic Magazine.
I think that's about it, for now.
--Jim