need to upgrade ram, need help fast please

My mom said she'll buy me RAM for my computer if I can tell her what exactly it is I want in the next 30 min...

I'm going to be searching the forums, but in the mean time if anyone can give me a quick response, it would be AWESOME and greatly appreciated...

I have a macbook pro 2.2 ghz 120 gb hard drive (just bought a 500 gb 7200 hard drive it will be here on wednesday)

I was wanting to upgrade my ram ... which ram should I go with (I don't know anything about it)

I just browse the net and play video games, but since my mom is buying, she'll buy me the best of the best, so any help on that would be awesome... please please help!

thanks!

PS the memory I have now is 2 GB 667 MHz DDR2 SDRAM....

 

please help guys and gals

should I go with 4 gb? or 6 gb?

one 4 gb card? or two 2 gbs?

pleaaaaaase!

 

what is this ? 4.0GB Upgrade Kit (2.0GB Modules x 2 Matched) CAS 4 High-Performance tuned low-latency

I ended up buying it, it was only a few bucks more...


I want to time my computer startup time with 120 gb full hard drive and 2 gb ram... then install the new 7200 500 gb hard drive and time it, then install the 4 gb ram and time it... should it increase a lot?