There are a lot of things that determine how fast a laptop is and how fast a desktop is, and it all depends on how fast you want your computer to be. Generally desktops are more cheaper (it is easier to upgrade and the parts are cheaper, and they are cheaper to buy) and laptops are more expensive (and are more prone to damages).
However desktops still tend to be faster than laptops because of a few key reasons, such as they have faster hard drives (up to 10000 RPM) and you can probably pack more memory into a desktop than a laptop. But there are laptops (with faster and bigger HD's and more RAM) that are as good as desktops but, they are really high end (so you'll end up paying more...).
So chances are that if you want a computer it is going to be a desktop and if you want a portable computer (i.e. not a desktop replacement as mentioned above) then you are most likely going to prefer a laptop.
(BTW Trisha, who needs HP support or best buy geeks when you've got SysChat
!)