You can pick anything
Generally speaking Ubuntu does a pretty good job at supporting most of the hardware you'll find in common laptops. I've been using Linux on various laptops since 2007 and I've only come into a problematic hardware once.
I had issues with
Nvidia Optimus. It's a video card sometimes found in laptop. Some things to note:
If you're worried, take a look at certified hardware
One of the great things that Canonical (Ubuntu's publisher company) has been the first to do in the Linux world is to run a
certification program in partnership with manufacturers. Take advantage of it, there're about 500 models to choose from in there.
Note that this doesn't mean that laptops that aren't on this list won't work with Ubuntu. It simply means that professionals are testing Ubuntu on these laptops making sure they don't find any problem.
There are high end Ubuntu-centric laptops
Two new(-ish) hardware manufacturers deserve a shoutout for basing their whole strategy around Linux.
I particularly like System76 hardware. If you're lucky to get your hands on one, don't miss it!