An HTTP 204 response from your Arduino should result in no change of view in the client.
That seemed to be what the OP requested when he said this:
My question is does anyone have an idea how I could create a button on my html webpage that would not take me to that link but just simply send the information to board?
The iframe comes in handy when refreshing a pix justing javascript in a setup like below (haven't figured out how to write an applet or use possibly ajax).
http://web.comporium.net/~shb/wc2000-PT-script.htm
What happened to the buttons in your code? You don't like them? Every browser has Javascript if you enable it.
I took the iframe code out of the multibutton code just to keep it simple to just the buttons. Lots of clickable stuff, like the very old page below with dropdowns that controlled servos and a parallel port video switcher. The video frames were pulled via an applet, so the iframe wasn't needed.