Ok, but do you understand you weren't hacked?
The client generates new addresses automatically. It's going to do that regardless of whether you get a new wallet or not.
The bitcoins you currently own are in the original wallet file that was in that directory. So do not delete or lose that file.
No. I have been involved with BTC for a while and never heard of a wallet changing its address. My question remains... how do people know where to send money to me ( or anyone else ) if the address is changing?
I looked in the blockchain... and there is no connection with the new address.