Is a wallet specific to a PC or the wallet data stored somewhere in the cloud?
Wallet data is stored localy.
Yes
Its usually very realiable and I can currently reach it. Armory needs bitcoin core / bitcoind in order to work. You will also have to download the blockchain. You might want to get a torrent [1] for that.
A Wallet is a piece of software that helps you to manage your private keys. These private keys allow you to spend the coins that have been send to your addresses.
Sorry, I dont understand that. But google offers a service where you are dependent. Armory is something you do localy and you do not rely on anyone else.
Yes, almost all questions have been asked allready, but thats just the nature of things. As long as you show willingness to learn and read you will usually get an answer here.
[1] https://bitcointalksearch.org/topic/ann-bitcoin-blockchain-data-torrent-145386