WMP 10 freezing

Among other things I manage 4 stand alone desktops at home. My teenager has a PC using XP Pro w 256MB RAM (DDR333 PC2700)Asus A7V8x-MX w AMD XP 2K, 40GB HD using nearly half HD capacity and puts everything on the desktop. WMP10 freezes after any selection in abut 45 secs. Some books say you need 512MB but my laptop only has 256MB and runs without problems. I’ve defraged HD, gotten rid of any unneccessary desktop stuff, tried to eliminate competing programs but not sure I did completely. Any suggestions?