Another post asking for request, also boot time

Against my better judgment I am making another post asking you to request information of the same topic that is on the blog right now. My main concern is that anyone who is on the internet long enough to find this blog already knows most of all the information that I have put up so far. So please comment with information that you would like to know about computers or anything else in that matter (I find it easy to research online, actually learned some stuff when I did the screen cleaning post). But there was a question that I noticed in my previous post.
Though stopping programs from starting when you log on will make your computer respond faster when first accessing the main interface, it will have no effect on the speed it takes to get to the point where you log in. When you notice that it takes forever to get the point where you log on then there is only one thing (within my knowledge) that can cause this, which is minor corruption of system files. All other files are not accessed until you actually log on so the only way that I know how to fix this is Defragment the windows section in your (most commonly) C: drive, which is explained in a previous post. But if this does not seem to work and you don't have vital information on the computer (or a external drive that can hold all this information) it may be worthwhile to do a completely fresh reboot. Most computers come with a disk that you can use to safely reboot the computer and once it is done the information on the computer should be as clean as when the tower came out of the manufacturer.