Firstly, check that your laptop is connected to the correct wireless network - i.e. your own and not the neighbours'!
Secondly, computers may have two different ways to manage the wireless connection. One of them is the function built-in to Windows and the other is a program provided by the manufacturer of your laptop. If you are using the laptop manufacturer's own wireless connection software, disable it or uninstall it and use the Windows one.
It's unusual that you desktop gets a better wireless connection that your laptop. It's usually the other way round because laptops have built-in antenna either side of the display whereas desktops just have a USB stick. However, with a desktop you can have the USB stick plugged in directly or alternatively plugged in via a cable. If it's on a cable you can point that cable at the router, and that's why you're getting a good signal.
Try repositioning the router or even just its antennae.