Why does my screen keep freezing up so often?

I have a hp pavilion laptop with a Windows XP Home OS.It has a 60GB hard drive with 512 RAM and a speed of 1.73MHz.I've used up about half of the hard drive and have around 50-60 processes going on at any one time.Everytime I turn on a program I have to wait before clicking "ok" or "next" or the program with freeze up.My MSN Live freezes right away for the first 10 seconds or so when I log on.I've scanned my computer with Norton Anti-Virus 2005,Windows Malicious Software Removal Tool and Windows Defender and neither detected anything at all.I defragment my drive every 2 weeks as well.Why does this happen and how do I fix it?

Why does my screen keep freezing up so often?norton ghost

I doubt that any of your software is scanning for adware and spyware, try the norton spyware scan in the latest yahoo toolbar. You might also check to see that you dont have apps you dont need runing at startup.

Why does my screen keep freezing up so often?software

Get the model number and find out what the max memory that can be installed on your laptop. Computers put enough memory to run. Then when you start ADDING stuff, then you need more memory.

Anyway, this URLs will see what you have in your laptop. But you still need to check what is the max memory your laptop can hold.

INFORMATION SITES

http://www.belarc.com/free_download.html -- info on computer inside

http://www.cpuid.com/cpuz.php

http://www.crucial.com/index.asp -- info and price on memory