I'm a fairly experienced computer tech worker. While that does mean that I do know a good bit about PCs, it also means that I always see people's computers at their worst in terms of hardware failures. Keep that in mind when reading this post.
Toshibas generally have electrical gremlins, particularly the newer models. My own Satellite R20 has C controller issues that occur every time other than when I'm trying to send it in for warranty repairs, and I've seen numerous occasions when the LCD displays simply stop working until after a hard reboot. I can fix broken parts if they're removable, but you can't just go out and get a new laptop motherboard of eBay or Newegg. They're not horribly unreliable, but my next purchase will not be a Toshiba.
HPs come with bad hard drives from the factory. iirc they're either Fujitsu or Seagate. Either way, they develop massive seek problems that rob performance and lead to a slow, painful death. Not a fan of their operating system install either because it comes with a lot of junkware, but if you can format and build your own it's not a problem. Quality components other than the hard drives and junkware. Definitely worth consideration if you can replace the hard drive with something else.
Compaq is an HP brand, but they're junk. HP dumps all of their poor quality parts into Compaq and sells them for cheap. It's a good deal in terms of PR, since they can sell cheap laptops and maintain a brand name associated with quality, but that doesn't mean I'd buy one. Expect major hardware failures. Do not buy.
Avoid Sony Vaios unless you like unusable operating system configurations and poor build quality. "Frustrating" describes everything about them, be it service or everyday use. They look good sitting on your desk, but are functionally only good as lap heaters. When Sony does something well they do it really well, and when they mess up they mess it up really badly. Their PCs have always fit into the latter category.
Consumer-grade Dells are outright junk, but their business models are really good. Helped a friend pick out a Vostro for his daughter this Christmas and, while I wasn't too crazy about the touchpad, it was a top-notch laptop with great quality components and a good case. Like any laptop, touchpad quality and keyboard responsiveness get better with the higher trim models. You can get a very well-optioned Vostro (for everyday use) for under a grand, and that includes some cool stuff like an Nvidia graphics chipset and a decent N wifi card. I was disappointed at not being able to select an Atheros or similar high-end wifi card, but if you really want something like that you will probably buy your own anyway.
Little experience with Lenovo IBMs. I've heard the Thinkpad's build quality has improved a lot since the Chinese took over IBM, but I don't know anything about their customer service. Can't say I've ever had a problem working on them, other than the old IBM cases that were not standards compliant (not that any big-box manufacturer case is ever standards compliant).
Regarding the HP that OP picked out, it's not bad for the price. Not crazy about the 800mhz RAM; I'd get 1066mhz if you can find it. The 5400rpm hard drive is a bit on the slow side, and you might find yourself kicking it if you have slow RAM too due to it causing more persistent lag issues. That particular model doesn't appear to have any savings over the model you can get at the HP website either. I'd definitely spring for the ATi Radeon Mobility graphics chipset HP offers and a wireless N card; the Radeon will give you a lot better performance in Vista and Windows 7, since they're both graphics intensive operating systems and you don't want junk Intel chipsets bottlenecking your speed. It's not something like RAM or the hard drive that you can easily replace, so it has to be right the first time.
I also recommend against buying from Best Buy if you can help it. They're the Autozone of electronics in that they make their money selling junk to people who don't know any better. Not saying you don't know better, but a lot of people use them for sales advice and get bad service as a result. As I noted previously, they offer an inferior product at no savings over buying straight from the factory, and God only knows what they'll do to your operating system in addition to whatever the OEM does with it.
