What exacly does lnx4win (Linux for Windows) do to my windows xp pro os and can/how i COMPLETLY remove linux from my pc/windows?

If I remember correctly, all it does is create a couple of really large files into which the distro is installed, and from which the distro runs. There should be a 'remove lnx4win' program that came with it - check your C drive, and also check in the 'add remove programs' bit. It may also have added a few lines to your WinXP boot loader file... but I wouldn't know about that father!

Anyway, why do you want to get rid of it? Are you thinking of installing a complete distro onto the harddisk instead of XP? You got hooked, huh? Good to hear!

restore your full backup you made before you installed it,
with all that great windows backup and restore software.

Do you mean completely as in "get all your drive space back." or completely as in "destroy all traces of it so that
no one can tell it was ever on that machine?

In the first case, its been answered well enough above.
In the second case, you can't. Windows knows you
had linux on there, and it'll get even. Now or later. or both.

If its mandrake, its probably in a directory called mandrake. Everythings there. There's not a bunch
of linux.dll's and mandrake.ini's scattered all over
drive like windows software does.