Newb Questions on; Bitcoin-QT Client / Server, wallets, Calculator

Hiya all, great site here. Suppose I'm now with the larger group now investigating bitcoins more intently. Upon reading up on this recently; I realized that I HAD looked into mining briefly a couple years ago. Believe I turned away at that time from low value (I know, tend to have bad timing like that).
To try not rambling I'll get to some questions; I'm having trouble finding. If there's a post already covering this, could you please refer me?

1. I DL'ed and synced the Bitcoin-QT client. I DID encrypt and have backed that wallet up (0 btc). I then tried starting the -server; I noted a NEW sync and my one pre-made address was different. This worried me, so I shut off server and went to normal client. Shows encrypted and sync'ed. I then checked AppData to see there is still ONE copy of wallet.DAT.
Questions:
-Does the QT client AND sever both SHARE a single wallet?
-will there be conflicts to this?
-Should I run client wallet on a separate PC than server?

2. In order to see if my client was working I've generated, copied and pasted an address to a couple faucets (.0001 or something). My hope is to see some sort of transaction to confirm I'm doing it right. None so far though.
Questions:
- Do I generate a new address for every transaction to receive?
- Is using faucets a good way to see if I'm setup correctly? (as no transactions shown in yet)

3. I note people using / suggesting calculators and have plugged in some Mh/s numbers to see they payout in coin or dollars per day.
Question:
- Are these calculators figuring payout in a Pool?
- If someone is solo, am I correct that they award these coin blocks, not partial units?

Sorry to ramble, I'm sorry for super noob questions as well. I'm sure I'll have many more; but am trying to read what I can.

Thanks for any help one can offer

EDIT: removed question on bitinstant as I found support thread for it