jQueryUIConfirm is the best option to combine jQuery UI dialog as affirmation window on an Asp.Web web site.
You may embrace html into window’s message, customise the title and the textual content of the buttons. This management will be included right into a bindable management (Repeater, DataList, ListView, ecc…), and it robotically sniffs any validators you’ve placed on the button.
And it’s absolutely themeable by requirements jQuery UI theme, it exposes practically each jQuery UI configuration property.
Replace 21/02/2010: Mounted a bug involving masterpages.