It's not a stupid question at all. Gearing is multifaceted as there are a lot of paths to gearing. Since you don't look to be playing any PVP, I'd suggest focusing solely on farming Vangaurd Rep & Marks and don't worry about the other Factions; you need Crucible Marks to buy anything they're selling. I agree starting with Boots is good; but you are running a Titan and the overall best Exotic armor piece is The Armementarium (I have it; give it look). I say "best" because most Exotics lock you into one subclass, but this piece does not. It's equally awesome for Strikers & Defenders. Xur's sold it multiple times; 3 out of the last four weeks, I believe. Strange Coins do come from the Weekly Strike; 3 difficulty levels each award you with 3 Coins. But if you skip, say, the lvl22 and just do the lvl26 you'll get 6 Coins; they "give" you the 3 from the lower level version you skipped over so you aren't forced to run the same Strike multiple times just to get your 9 Coins. So run the version you can do the easiest; you'll get the Coins quickly enough.