your ideal or application in this case is very wise (too wise )
but .. your sis system would not work (windom Xp ) without the mac os X...

all mac pc need the original mac OS .. to boot up the mac system 1st...

and the apple mac osx are very iitelligent is their own way ... one mac os only can run on one mac pc .... meaning that when you install the mac os it is only good for that particular mac pc ...
cos the mac os always update you with the latest firmware from their support system ... so .. with the mac os install .. it read your pc system serial number ....

i hope this can be helpful to you ...

I am a pround owner of imac G5 and a powerbook G4... so to say I am having two sets of Mac OS X ...

as the quote by "xaw5126" regards to the "wrong Infromation" I would like to just clear the air a little bit ......

with the two copies MAC os X that i am having .. i could not just simply... install it on other mac system as i like .....

tricky : Yes .. one can always install the copy of MAC OS X in any mac system BUT the copy that come with your MAC system IS only good for that particular system...(cos it read your system serial number for what so ever latest update on ALL the appication in your mac )

unless .. the copy that you have it is a stand alone (Mac os X ) and it is NOT the MAC OSX that comes with the system .....

so ,... in this case ... the person whom asking this question is intending to use his sister mac system Mac osx ....in another mac system ... !!!!

it is a very very doubt question ... :

I would be sure .. if you were to answer MAC personnal ... the answer will be a straigth NO NO