I will be travelling from Canada to Singapore via Shanghai Pudong, on China Eastern Airlines. Our layover will be 6-7 hours.

Is there a transit lounge in Terminal 1, or will I have to collect baggage and/or go in and out of customs and/or security?
Do the shops and cafes accept US dollars at reasonable rates, or do we need yuan?
Are there any airport lounges we could pay for, to get a little rest and possibly wifi?

Any advice gratefully received.
Chris