Linux is not user friendly like a Windows PC or a Mac. PC has eveything the others have and more.
wine ftwms paint will work on ubuntu
Common misconception, I would quite happily setup a complete pc beginner on something like Ubuntu, fair enough it can be tricky sometimes on linux to recompile some program or change some of the other backend settings via the terminal, but for the average user they wont notice a difference between this and windows. Especially with gnome 3 now being released, once that comes to Ubuntu I think it will actually bring the best bits of windows and mac to linux desktop. Obviously if you want to game then its not worth it, btu for the average user linux is a brilliant way to go. and most deffinately user friendly.
But there is still no advantage for the average user to use Linux. A beginner would soon run into problems, with program compatibility and what not.
I dont think the average user would have problems at all, the average user looks to surf the internet and use a word processor, also probably email, view photos, play videos that sort of thing. The "average" pc user doesn't do anything that would encounter any compatability issues on linux.
I think the problem is that Linux is too often thought of as the still too complicated OS that it used to be. Ubuntu 11.04 is incredibly easy to use, if I was installing a new pc for parents or grandparents or friends that wanted it for the general browsing word processing etc I would without a doubt install Ubuntu over windows.
If linux had full game and software compatibility i would most certainly replace windows with it, wine just doesnt do it for me