Need a new computer. Help

It is time to say good bye to my five year old, 1.5GB memory, 80 GB hard drive HP computer. I would value your opinion on what my new computer should look like.

Dell has the XPS 8300 with Intel Core i7, 8GB memory, 500 GB hard drive for $700. I have never owned a Dell before.
Is that a fair price? Should I be looking for something else somewhere else?

I would like to get a computer that will not have to be replaced for "a long time".
My price range is $500-$1000. Thanks.