Desktops are generally faster, but less portable. Laptops are generally a bit slower, but are more portable. It really depends on what you are using the computer for. If you travel, you might want a laptop. If you don't travel much or you just don't need your computer when you do, a desktop would be your best bet. The size of the laptop will cost you speed because there is less room for high end parts which are usually larger than the normal parts. If you want to game at high FPS, I would recommend a desktop. If you want portability, go with a laptop. Laptops also cost a bit more because of their size.
