I'm a fan of Acer products, they've all been very reliable and generally well-priced. The Aspire series of notebooks seem to be the "replacement desktop" laptop of the Acer brand. Mine was a monster but I'm noticing smaller ones while searching - also with more RAM then mine had, which is awesome.
I found two within your budget on Newegg. Both 15", both with decent graphics (though on-board is generally a bad idea for gaming, it is just fine for most other applications), dual-core processors and "super multi" DVD drives (I had to look this one up, the name seemed superfluous. Turns out it just means it reads/writes all DVD formats.).
The first link is for an Acer Aspire AS5253, it's $449, has 3gigs of Ram, a 250gig HD and runs an AMD processor.
http://www.newegg.com/Product/Product.aspx?Item=N82E16834115979The second is an Acer Aspire AS5742, it's $479, 4gigs Ram, 500gig HD and runs an Intel processor.
http://www.newegg.com/Product/Product.aspx?Item=N82E16834115994Obvious differences are the processor brand (which doesn't matter all that much and is more about preference) and the size of the RAM and Hard Drive. So - how big a drive does she need and will she be running a lot of programs at once?
Hope this was helpful -