Modification on my keyboard

Hi,

I would like to change a task of a key on my keyboard on Windows XP.
Precisely, I would like to change a key (for example, F6) to a new function
which ''MINIMIZE'' a window and another key (for example, F7) to a new
function which select the windows beneath the windows I presently use.

These keys exist on my Sun system (UNIX) at my office. There is two key, one
named ''OPEN'' and the other one is ''FRONT'' and do exactly what I have told
you above. I found those keys very useful and I would be happy if I could use
something like that on my Windows XP at home.

Thank you in advance,

lyca0n