Welcome to Flyertalk, csm634s.

1. Sounds like your best bet would be one of the AA cards and the SPG card. Or, if you can get both a personal and business AA card and meet their spend requirements, that would be the way to go. You can transfer SPG points to AA at a 1:1 rate, with a 5,000 mile bonus for every 20,000 points moved in one transaction. But the SPG card doesn't offer as generous a sign-up bonus as the AA cards, so if your goal is to get as many AA miles as you can, that's the way to go.
2. Pretty much the only way to get elite status on AA is to fly (or achieve lifetime status, which assuming you're starting at 0 miles is going to take a while). Since you're probably not going to fly 25,000 miles in the next 12 days to get the lowest-tier status, you'll want to wait till next year to start your status chase.
3. Your question is very broad. For others to help you, we need to know what your flying patterns are (who you fly on and where you normally fly to) and where you eventually want to get to.