[Arubalisa]

The US dollar is accepted everywhere, including taxi cabs.

Taxis accept cash, but do NOT accept credit cards.

http://taxiaruba.com/new/farelist.html
http://taxiaruba.com/new/policy.html Be aware of policies when traveling on Sundays, at night after midnight or to and from the airport.

Additional taxi info http://www.aruba.com/forum/tags/taxi.html

Will we always be offered to pay either dollars or florins including use of credit card?

Use US dollars. No need to convert any of your cash to florins.

Do the cabs have a meter or do you negotiate a price?

There are no meters.
Taxi rates are regulated by the Aruban Government.
Print and take with you the fare list at the url above. Due to the high price of gas, some taxis have resorted to "making up" their own fares. Agree on the price before you step foot into the taxi in accordance to the fare you will have printed and taken with you. If they do not agree, and perhaps try to give you a "story" that fares have changed, it is just that, a "story". Fare changes have been proposed, but have not yet been approved by the government.

Do cab drivers accept a credit card?

No.

Is it advisable to carry cash or bring traveller checks?

If you are more comfortable with traveller checks, cash them as you need to at your resort's front desk. I have never heard of a taxi driver who accepted them. Pehaps some do.

I'd rather have little cash and use a credit card

Taxis do not take credit cards.

We're excited about going but have not had to deal with currency issue except for travelling to Europe which we have not done for a number of years. Please set me on right track. Thanks!

You will have zero currency issues. Go and enjoy!