Admin, I don't think the pagefile actually clears with shutdown and less you have it set to do so. I just can't remember where it is you are supposed to set it, but can probably be found in the registry if nothing else. Mine is set to Windows XP controlling it and for some rewason I haven't noticed it on this computer. However, my girls have said that it does seem a little bit slower, but only after I asked them. If it really was bad they would have told me to fix it.
Sam I did notice that all of your video cards are 64mb or less. this could also cause some slight slowdown.