If you got an earlier version of windows operating system (3.1/95/98), then go ahead get the SE upgrade cd.. search pricewatch.. some people are selling SE disks for $20. That was teh actual price of the CD when it first came out from microsoft...I believe it doesnt have ICS though.
You can do a full fresh install from an upgrade cd. If you dont have an OS cd.. borrow one for a friend, and you will need it for a minute only.
Start the install from DOS, typing setup and then when asked for a qualifiying CD.. pop in the other cd and then point to it.. now your home free.
Since the EULA doesnt state that you have to have a original cd to get teh upgrade working, it will be worthwile.. plus its legal, you do have a copy of the operating system .. its just an Upgrade cd.