Okay so I'm pretty experienced in HTML and CSS and such.

I need a form of some kind that will have the following functions but don't know the best way to go about it, it's for choosing a template design, it will have a demo and preview links under each image.

Is there any quick easy form maybe even using java that will send an ID number to text field? User clicks the image and it assigns the value to a text field in a form.

Is this a good way to go about this? What would be the best possible way to create a user friendly template chooser. Here's my basic idea:

One image, Demo and Preview link underneath thumbnail. Maybe on the side or under the links a couple of colored boxes 16 x 16 to choose the template color. On click of image, writes to field Template Number. The colors also on click write to the field Theme/Style. Then in the actual form it will have various fields like their username and such.

I'm using Joomla 1.5.15 is there a way it can automatically write their username in for them? I don't know, I have tons of ideas but no heading so please help out!