primopdf is a great user friendly and FREE program. Like beth said- sometimes one needs a little more than the basic. IF that is the case and you still want FREE- try
pdf995
This is a full feature pdf creator, manipulator, editor etc...... It is totally free. The free version only has a small ad that pops up at the begining- thats all. To get rid of the ad- the whole suite costs $19.95. I have been using them for years (the FREE version) and have had zero problems with it. Great full feature program.
JUST and FYI
Andy