well if you are just wanting to free up space, go into your control panel, go into add/remove programs, remove any apps/ etc. that you rarely use, besides your drivers and other windows updates, etc. and then afterwards, go to my computer, or computer, as it says on Vista OS's, and right click it and go down to properties in the drop menu, it will have an option to compress files, check that and click apply, may take several minutes or so, after that, use disk cleanup...also found on the same window..check all the boxes when it pops up what you want windows to cleanup...will also take sevral minutes or so, depending on how long its been since you've done this, then afterwards, click tools and go to defragmentation, do this also, as it will compact fragmented files and create more and also make more programs and such on your hardrive easily accessible....but i still recommend doing my first method, is a lot better.