As a system admin. and technician, I would advise heavily against buying a computer from a department store. Most employees know nothing about the product, except for how to place it in your shopping cart. If you have a good general knowledge of computers, go to a local business, customize it on your own, and have someone else do the "dirty work". If you are indeed hell-bent on buying it from a name-brand company, Dell has had the least number of technical difficulties, and has been rated at the top in terms of customer service.
I hope this answers your question