First TFOL to reply!
1. Male (ahem, not boy!)
2. 14
3. Lord of the Rings.
4. I caught onto LoTR right after watching the Hobbit, and all three LoTR movies in 2 days. Lots was packing into that, but I watched them all 3 times after that though. Sames goes for SW. I was interested in Castle before SW, so after I watched the movies, I started playing and building the sets! I sort of don't think that that strategy works for all themes, though.
5. Long lasting! It's hard to spend 6 months on a LEGO forum and get bored of it! As long as I have money in my sets, I will stay interested...trust me!
To answer your first few questions, I first started out with the accursed DUPLO very young, and often played with my cousins and friends. Then I moved onto LEGO's when I was 7 [that was when I received my first set, but I obviously played with LEGO before that!]. First came a theme called Jack Stone, which is aimed at ages 6-10. I stuck with that for about 2 years. After that came Knights Kingdom, for 2 years. Then SW...then LOTR!
I personally build, then put on my shelf. It's sort of running out of room, so I have to improv and stick some builds closer together than I would have wished.
I started investing in late-December/early-January after the USA Today BrickPicker article. Prior to that, I had been combing eBay for hours and hours looking for deals, especially keen to find a used Clone Turbo Tank. Never did, but I moved on! That period, which lasted about 5 months, basically was my stepping stone into LEGO investing. It really helped because I knew at least a bit about LEGO and vaguely what a good deal was.
Hope this helped!!