Taking my iMac to the Apple Store's Genius Bar - lots of questions

It's looking more and more like my iMac is sick and it's time for the Genius Bar to have a crack at it. I've been to Apple Stores before (including the new one in my area), but I've never needed the Genius Bar.

So, a few things I need to know before I go:

1) Do I bring just the machine itself, or do I also need to bring peripherals, drives, etc.? Any paperwork (receipts, AppleCare agreement...) I should also bring?

2) Is the Genius Bar free? Is any cost resulting from their work covered by my AppleCare? (I have about 6 months remaining on this machine.)

3) Does the Genius Bar take appointments? This being the holidays, and this location being a very busy (and posh, for here) shopping center, I could have a long wait otherwise.

4) If the iMac needs to be sent in to Apple for service, can the Genius Bar package it and ship it for me?

5) While I'm there, should I buy a Mac Mini and an iPod Nano? (OK, that one's only half-serious.)

Any other advice on this is also appreciated. I want to make sure I have everything I need before I go - the nearest Apple Store is a 100-mile roundtrip from home!

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