I'm often asked to recommend notebooks by intending purchasers.  Intelligent
well informed people find the multitude of choices and conflicting claims
confusing.  If I make a bad recommendation then I'm risking eternal punishment
in the form of desperate calls for support at all hours of day and night.

I'm sure that many of my cyber breathen have been in such a predicament.  So
here's how I go about it.

The most important thing to remember is that manufacturers optimise their
hardware to suit the OS, so making changes opens a big can of worms.  This is
expecially true of the cheaper notebooks which are often engineered to a price
point and thus require drivers for less common devices.  Making big changes is
like buying an Audi and deciding that you like the BMW engine better so your
swap them over.  Neither car is going to get any better unless you are very
experienced automotive engineer.  For backyard mechanics, it could be a very
expensive experiment.  So too it is with notebooks.  You can install a
non-manufacturer supplied OS, but you may need to tinker to make it work
properly, all of the time.

First question is whether they use a computer at work and how much.  With rare
exceptions people who don't relish fiddling with their computer  are loathed
to learn something new.  In that case, I gently suggest that they go with the
devil they already now.  In most cases this means Windows and I typically
recommend they stay close to what they are already familiar with.  Of course,
this is not much help if they are using Windows ME on a 8 year old PC at work.
Don't wince!  There are more of these out there than I'd like to believe. 
Many small businesses place greater priority on the owner upgrading their
wheels or yacht than the PCs the staff have to put up with.

Some people want to edit videos, organise their photo and/or music collection.
I suggest that they may want to check out the local Apple store and see if
they like what they see.  If these folks are experienced with Microsoft Office
I do recommend that they consider a Mac version of it.  The idea is that they
will only go ahead if they are comfortable with the store's expertise.  Not
surprisingly many people suffer sticker shock after having looked at cheap
notebooks at the local discount store.

Do I recommend Linux based systems?  Yes, but very cautiously.  I do suggest
that they check out some of the notebooks that come with Linux pre-installed.
But typically, they don't compare well with the flashier Windows or Mac
systems on display.

Although, it seems that everyone ended up buying a cheaper Windows based
notebook at least I've managed to avoid the majority of support calls.  For simple
problems I suggest workarounds.  For serious problems I recommend that they
get the shop they bought it from sort it out for them.  They made the profit, so
they can fix it.  Surprisingly, nobody has disagreed with me to date.