Finding a School Laptop, $750 range

My sister is looking to purchase a new laptop to replace her four year old Dell and she's asked me to price one out for her. While I'm fairly experienced at building desktop computers, I've only ever bought two laptops, and I'm not sure what the best choice would be.

She isn't a gamer and doesn't need a huge amount of system power, but it should be good enough to run modern software and avoid slowdowns with a lot of Office programs open. Good hardware and a solid extended warranty is a must. I'd also like to find something that's fairly light and easy to carry around. I'd like to pay around $750, but I'd be willing to pay as high as $1000 if necessary.

Any suggestions? Brands I should be looking for, or specific laptops that meet these specifications?

Thanks for any help.

The Dell Inspirin is a good laptop and you could save a bit going with the AMD CPU. From carrying standpoint a 15'4 would be your best bet. The alternative would be checking the Sunday sales at BestBuy and Circuitcity, Toshiba has a good reputation and they are often on sale. Might be a bit cheaper. If I were going with Dell and could afford it, I'd upgrade the intro level AMD CPU one level, get at least 120GB and even better a 160GB hdd, and add a a GB of RAM once you get the machine, Dell's prices are really high for memory. Keep in mind it's a lot more expensive to upgrade a laptop compared to a PC so you're generally best getting what you want.