Sorry Tech, but I have to correct you
What he means is that little 'slider bar' when you boot windows XP. At that time Avast isn't even loaded.
parachutestx, in time you install more and more applications. Almost all of them are changing Windows (eg: the registry) that is causing the longer boot time. Only thing you can do about it is, installing Windows and the applications you need/want and create a image file of the drive and put that image back instead of just removing a application you have tested. This is the only way and it is caused by the way Windows is working.
About the memory:
Windows is not very good at releasing memory that isn't used anymore. I remember that with AOE (Age Of Empires) this was a serious problem on XP systems. A reboot was needed to release the unused memory. Again something you can't do a thing about. It is up to MS to fix these kind of things.
