For xpdf (I don't use kpdf it's too slow and hate the integration into kde):
The main configuration file is in ~/.xpdfrc
Rename it to .bak and launch xpdf.
currently my .xpdfrc contains this:
The only thing that exist in xpdf is the bottomline:
The arrows for moving one page back and forward, a place where you can directly put the page number you want to jump to, the size, search and print.
There is no menu, no toolbar.