There are some NWOBHM bands that have stood the test of time (Iron Maiden, Judas Priest, etc) but a whole lot of bands were only really popular in certain communities. I think the Internet has brought back some of the popularity, but I don't think it's all too popular.
BQ1: I played a Judas Priest song on Guitar Hero and I really liked it. I had heard of Def Leppard before that, but only their cheesy Hair Metal stuff, not their earlier stuff.
BQ2:
- Iron Maiden takes the cake on this one. They're amazing.
- Diamond Head's "Am I Evil" is one of my favorite heavy metal songs of all time.
- Angel Witch is also a classic, their self-titled album is great.
- Witchfinder General mixes in doom metal influences and I love that about them.
- Raven made really energetic and upbeat metal which I think is fun to listen to.
- Saxon's self-titled album is one of my favorite metal albums, the Rainbow Theme and Frozen Rainbow combination is amazing.
- Judas Priest was better in the 1970s but they still deserve a mention.
BQ3: It used to be one of my favorite 'genres'/movements but I've grown out of it since. I rarely listen to any of the bands I found other than the ones on that list. I rank NWOBHM fairly highly but if you asked me a few years ago I would have put it right near the top.
BQ4: Well, I really liked Classic Rock for a while, and I feel like NWOBHM music built upon that and made it heavier and more intense. It was just the next logical step for my musical taste. So I really enjoyed the added intensity, which led me into the "extreme metal" genres (Thrash/Death/Black/etc) that I've enjoyed. NWOBHM is just really raw metal, without gimmicks. The aesthetic is really cool too. But yeah, NWOBHM's real cool.