Changing Emacs font

[Jai Dayal]

Hi,

 I want to change the default font to be Monospace of size 12.

When I open emacs -nw in a terminal, the terminal's profile preferences are
set to Monospace 12, however, when I open up emacs without a terminal, I
get a completely different set of fonts, and frankly, they're hard on my
eyes.

How can I change the emacs settings so that the font displayed is Monspace
size 12? I tried all solutions under "Globally Change the Default Font"
found here:

http://www.emacswiki.org/emacs/SetFonts#toc2

But I've had no luck.. the font is still the same original one.

What am I missing?

Thanks much!
Jai