Mate you can slipstream SP's but you canot slipstream hot fixes, and there is one program with wich you can preinstall all SP's, Programs, Hot Fixes, and program is called PEbuilder and it's freeware here check it out :
http://www.nu2.nu/pebuilder/
EDIT: I just remembered thet you slipstream service pack in to a windows installation to have this working right, don't know how much do you know about slipstreaming but even if you don't know anything click
here to get help!!!