Hi :)

Windows Users are not always capable of installing a simple program. From my experiences i would estimate that perhaps 10% or less are capable. However, when they move to a linux system and eventually find a package manager they seem to feel a lot safer and more capable.  Windows users that cannot/dare-not install a simple program are unlikely to grok virtualisation and it's superiority over a dual-boot.  There are even a lot of linux users that have not really appreciated the benefits of virtualisation yet.

Windows is not an easy system to navigate around or back-up.  Give an average Windows user a camera, lets say a Kodak camera and let them try to get their photos onto their computer. There are various different packages in Windows that make this easy for them, "Put the CD in the drive and click 'next'" or sometimes just plugin the camera and 'magically stuff just happens'.  Now try to find where those photos are kept in the file-system.  Another example is when a Windows user sets up lots of templates for a package such as Excel (obviously a fairly advanced user!).  Try finding those in the Windows file-system!  While you & i may know where those are generally kept it is not intuitively obvious and even tho i know where they are likely to be it is still a pain to dig around the system trying to find all such things even where the Windows user has bothered to let me know they have used a particular device/package in a certain way. 

As an example, my aunt paid a well-renowned data-recovery service (nothing to do with me) to transfer ALL 'her stuff' from her old machine onto her new one.  After a quick flick around her machine was happy that everything had been copied over.  She wanted me to find a good home for her old machine but i advised her to hold onto the machine for 3 months and we had an argument because she was 100% certain that everything she wanted had arrived on her new machine. 2 months later i got the inevitable email asking me where all her photos were.  Luckily i had not been allowed to touch either her new or old machine so it was clearly not some sabotage on my part.

Another example, a company wanted me to reinstall Windows on various ancient old machines with inadequate ram (512Mb didn't cover all packages they typically had open at any one moment, one of which stated clearly that it needed 512 minimum on it's own). They made a big fuss about not copying any files from the machines existing file-system "because everyone saves everything to the server". About a week later i was expected to magically produce all the files that had been stored on the machines.  Luckily i was able to do this because i had disobeyed the direct order from my boss and had backed-up the systems on my own machine at work.  The result was that i got fired because i had disobeyed direct orders.

So, Windows users do not always know where they store everything.  Even professional computer services don't always know.  Simply copying the contents of their equivalent of "/home" is not adequate for ensuring everything is copied between one install of Windows and a new install of whichever OS (in linux the rsync command is good at even retaining the permissions of the transferred files).  

Yes, people 'should' use a separate hard-drive or even just a separate partition for storing data but that is incredibly unwieldy in Windows. In linux of course we can just move the /home folder onto a new partition and setup fstab to use it as part of the normal file-system.  In Windows you have to hack the registry or put up with constant annoyances with short-cuts (links) that don't quite work reliably.

Wiping an existing install of Windows and replacing it with linux ensures that any lost data is seen as a problem created by linux (unfairly but that's the perception). That is one reason we hear FUD about lost data.  Of course if Windows is reinstalled and data gets lost then people don't talk about that often because they then feel it shows them up as bad computer-users, also it's difficult for them to understand or express clearly.  Blaming linux is easy for them.  

The simplest work-around when installing linux is to setup a dual-boot (perhaps set grub to a very short time-out so they don't see the menu if you must).  Of course Windows does not easily offer this option either.  Since the Windows license/product-key can be used twice on the same set of hardware, both with Windows as a dual-boot and with Windows in a virtual machine you could try that but wiping an existing install on a machine where the user doesn't know where all their own data is seems unnecessary.  Personally i would avoid installing Windows at all, my aim is to get people using linux, not Windows.

Perhaps give it a few months before asking the person whether they still ever use Windows and ask them if any stuff appears to be missing.  Otherwise it's just chalk up another person spreading FUD (probably behind your back) about how it is linux that lost data, not their bad usage and certainly not Windows fault for scattering stuff around in obscure places.

I feel i should apologise for using the term linux instead of gnu&linux or gnu/linux.  It is in common usage though and adding "gnu" to the front seems to persuade people that it is better to stick with Windows because at least no-one objects to saying Windows. Despite the FSF saying that the OSes should be referred to as "gnu divided by linux" (gnu/linux) i feel that it somewhat inaccurate too.  It is really "gnu added onto linux" or "gnu with linux" or "gnu and linux".  Since Torvald's doesn't make a fuss about such pettiness we get a few people trying to force us to use gnu/linux but really i think we have more important issues to concern ourselves with, such as increasing the percentage of gnu&linux users.  

Making things unnecessarily complicated is not helping, we have to deal with "what is" rather than the way we would like things to be.  Part of this surely has to be to show that we can work with existing systems? (Which is another thing that Windows cannot offer.)

Regards from 
Tom :)