Hey, It prob will work but you will be stung for charges on both sides of the fence. I still get charged for using a HSBC machine here with my UK HSBC account but it seems only from the UK which is 1.75 GBP for 2m VND but the exchange rate is good at the moment.
That reminds me of a work collegue of mine who used to say "I will not get naked" when on the phone being asked "to bare with me" tut.
Might try and give a TECHNOBANK ATM a try. You’ll still get charged at both ends of course, however you can withdrawal 8mil VND at a pop. If the funds are available in the machine. If not a screen will show you the max withdrawal limit. They charge 20,000 VND and my bank takes $5.00 for each withdrawal.
It depends on your card and bank :D. At least with Visa debit/credit card you ought to be able pay and withdraw money directly from your bank account with no extra fees, but this only works with some ATMs. Here's a list of ATMs in Hanoi http://visa.via.infonow.net/locator/global/ResultsDisplayAction.do?uid=X1116255-1300951443-ac130101
If you use the credit feature then there are fees to be payed. You could also get a prepaid card, which works like a ATM card. Hope this helps, but my advice would be that you talk with your bank.