If you must buy from Best Buy, don't get their warranty, get a manufacturer warranty. Best Buy is a pain in the ass and if your computer fails somewhere down the road, they won't give you a computer of equal current market value, they'll "determine" how much your old computer is worth today and let you pick out a replacement from that value. I know someone who had a $700 laptop for three years. It kept on failing and she had to keep taking it to Best Buy for repairs. By the time they let her replace it with a different computer, they said it was worth only a little over $300. She essentially paid $400 (plus the cost of the warranty, probably 150-200) to rent a computer for three years that wouldn't even work for more than six months.
Check with the manufacturing company, and see what their warranties state. My brother got to replace his computer with one of equal value after two years, which pretty much meant a minor upgrade and several system specs.
This is important for you not because you need good hardware in your computer to surf the internet, but because if a $700 computer can drop to $300 in three years, what will a $300 computer drop to over the course of 1,2, or 3 years? For the money, you're better off buying an external hard drive to back up your files in the case of hard drive failure.
Also, there are online retailers (both manufacturers and resellers) that have good sales that Best Buy never matches. PM if you want some suggestions on places to look.