Replying to First Laptop Help.

I am getting a laptop soon, and I was wondering if I could get your guy's opinions.

I need to get it at Best Buy because I have a gift card there, and I need it to be under $400.
I am just looking for one with pretty good RAM and a good harddrive. Preferably a webcam and built in mic.

Also, what is the difference between the memory and hardrive?
But,

So far I've been looking at this HP: http://www.bestbuy.com/site/HP+-+Laptop+/+AMD+E-Series+Processor+/+15.6%22+Display+/+3GB+Memory+/+320GB+Hard+Drive+-+Charcoal+Gray/2660188.p?id=1218342637618&skuId=2660188

But I don't really know what is different about that one and this one:http://www.bestbuy.com/site/HP+-+Laptop+/+AMD+Athlon%26%23153%3B+II+Processor+/+14%22+Display+/+3GB+Memory+/+320GB+Hard+Drive+-+Pewter/2284864.p?id=1218317762845&skuId=2284864 besides the price. if someone could tell me that would be great.

Also, If you've had experiences with any of these on this page:http://www.bestbuy.com/site/olstemplatemapper.jsp?id=pcat17080&type=page&qp=cabcat0500000%23%230%23%23205~~cabcat0502000%23%230%23%233d~~cpcmcat196200050013%23%230%23%231~~f1019||496e2053746f72652026204f6e6c696e65~~q70726f63657373696e6774696d653a3e313930302d30312d3031~~f305||24333030202d20243339392e3939~~f687||4275696c742d696e2057656263616d~~nf628||3330304742202d203439394742&list=y&nrp=15&sc=abComputerSP&ks=960&usc=abcat0500000&sp=-bestsellingsort+skuid&list=y&iht=n&st=processingtime%3A%3E1900-01-01
and think that one of those would be better, just tell me.


All help appreciated! :D