I would estimate (from a relatively well-informed position) that about half the serious issues that users face are due to hardware interactions. You'll remember that a few years ago the famous example was WIFI chip-sets.
The reality for the distributions is that if there is good support from the component manufacturer and the OEM then you can provide a good user-experience. We put massive effort into enablement with manufacturers such as Dell, HP and Lenovo [1].
As a user the best thing you can do is to buy hardware with components that will work. In the old days that used to mean looking at hardware component and comparing them to whether they worked with Linux. Now we have certification sites.
The second sort of problem is the general end-user issues. I actually think that Ubuntu is beyond the point where you need to open the command line for normal end-user activities. The big weakness there is that there's no equivalent of the 'Genius Bar' for Linux users.
I guess I was lucky in that installing Ubuntu on my Acer mostly just worked. I had some problems, which were not easy to figure out as a Linux rookie, but some help from forums and installation of some proprietary drivers were enough to give as good of an experience for casual use as I was having on Windows.
Since I installed Ubuntu initially out of necessity, I never really had the time to consider whether my hardware would be supported or not.
The reality for the distributions is that if there is good support from the component manufacturer and the OEM then you can provide a good user-experience. We put massive effort into enablement with manufacturers such as Dell, HP and Lenovo [1].
As a user the best thing you can do is to buy hardware with components that will work. In the old days that used to mean looking at hardware component and comparing them to whether they worked with Linux. Now we have certification sites.
The second sort of problem is the general end-user issues. I actually think that Ubuntu is beyond the point where you need to open the command line for normal end-user activities. The big weakness there is that there's no equivalent of the 'Genius Bar' for Linux users.
[1] http://www.ubuntu.com/certification/