I believe you can, in fact, upgrade the RAM in your HP laptop at the time of purchase, if you buy more RAM while at the store, and hand it to the clerk. He may look at you funny, just ask him to put it on. If he knows how, he will do it.
It is impossible to upgrade any type of VRAM, whether it be a laptop or a desktop. That's because the VRAM is built into the GPU/graphics card, so unless you're willing to try and switch your GPU...
I have added 2 x 2GB in my HP pavilion laptop. You need to know what RAM it is, DDR2, DDR3..? If you take your laptop (or RAM) to a computer shop, they will tell your what RAM it is and how much it...