It means you have to install the disk (As far as I know). I'm also not 100% sure, but I think you can't install later expansions unless you have all the previous ones instaled, i.e, you can't install CoP unless you have Zilart installed, therefore you can't install ToAU unless CoP is installed. Like I said I "think" that's how it works, but I'm not 100% positive.
As far as farming, it's kind of pointless asking people where to farm. TBH if someone has an awesome, high gil making spot, the last thing they're going to do is share it with others and ruin their market. The economy has been deflated a great deal in the last year or so, those same onions now may sell for around 5-6k a stack. It balances out though in that a Scorpion harness, for example, no longer costs 2mil gil, it's more like 130k-ish.
Really the best way to make money with BST is just xp. You'll get a ton of Beastmen seal's as you level and you'll be able to use those to do BCNM's. Barring that, most low level farming stuff you remember is still popular and still sells well, wild onions, beehive chips, silk threads, etc, so the areas you remember being viable farming spots will still work. Konschtat Highlands (sp?) was always my favorite low level farming zone. Sheepskins (crafted into sheep leather to make room) and other sheep drops, beehive chips, lightning clusters, Ram parts, and also the chance to bag Stray Mary and her Mary's Horn (200k or so)
Good luck and welcome back