DMail is correct - the title bar, etc all come from the window manager (e.g. KDE) and to change it (or get rid of it), you need to talk to the window manager.
In general, you'll use the Xlib call "XSetWMHints()". But it really depends on your code.
a) Read this link:
b) Post some specific code (please be sure to use "code tags"! ;-)) if you need more help.
Your .. PSM