Preferred methods of implementing screen labels and decorations

[52mid...@gmail.com]

As mentioned in earlier posts, I'm using FLTK to create a "PC Oscilloscope" and so need a Front Panel. I've used box frames to draw borders around control groups, and labelled boxes for control labels. Some of these provoke "unused variable" warnings from the compiler - not a problem - but as a novice GUI designer it makes me wonder whether I've adopted an optimum solution. A screenshot can be found here (please excuse the prototype "clunky" appearance):

http://52midnight.com/tmp/SNPS.gif

I'm aware that other methods exist, e.g. using background pixmaps over which the FLTK widgets are drawn, but would much appreciate the advice of those more experienced.

What is the preferred - or least CPU intensive - method of implementing such things?