Instead of playing with a button generating program, why not experiment with the built in Flash animated buttons that Dreamweaver has ?
Click on Insert, go down to Media and select Flash Button. You can choose from a bunch of different shapes and colours and you add your own text, alter the font size, style and colour as well as the button background colour.
You can join the Macromedia Exchange for free which allows you to access loads of Dreamweaver add-ons, one of which is a Flash button pack with extra designs.
Content for your site is the thing you should concentrate on rather than buttons. To be honest, I've yet to see a button generator I'd be entirely happy to recommend and most of them are template driven.
Any good image editor, your time and a dash of imagination are all that is really needed and you can create your own buttons.
Dreamweaver features excellent support for rollover effects, where you can use two different images to create a hover effect when your site visitors move their cursor over your buttons.