26000 khash\s is slow isn't it? It's not even worth trying to make Bitcoins, correct?
at that hash rate, you will get (mining in a pool - solo is out of the question, obviously) one Bitcoin every 17 days.
that's running 24/7; with your mining program set to max, so that your computer will be essentially unusable.
if it's an old 'puter, and you have another, and you're not paying for electricity...?