"....anything more than the norm".
What are you trying to do, exactly?
Have you installed any new software since you bought the machine?
Presumably the problem existed before you added the RAM - was that purchased from Packard Bell by the way?
You don't say how recent this purchase was, but a computer that's constantly freezing in normal use isn't going to get better by itself. My advice, subject to your answers to my questions, is to get the computer back to PCW very quickly.