HP has three basic lines of laptops. The entry level consumer model sold at most big box stores is the HP Pavillion. They use a fair bit of plastic and not a lot of metal, and tend to be a little heavier/bulkier than the upper models.
The next level up is the HP Probook which are featured on this page. They're a good, solid, all around laptop, nice and light, with good battery life, and a one year warranty. They're also very upgradeble with lots of storage and memory choices.
The very best laptops HP offers are the Elitebook and Zbook lines. We primarily sell the 14 and 15" Zbooks, and can be configured many ways with all sorts of drive and memory choices. They're the thinnest, lightest laptops HP offers, made mostly from solid machined metal, like Apple's Macbook Pro line. In fact, at certain angles, you'd think you are looking at a Macbook. The Zbook warranty is a full 3 years, with on-site options available as well. They are also built in a very modular way, and are very easy to work on.