From what I can see you defintely need to shut down some of the processes, switch them to manul, their probally is some program conflicts..which would not suprise me..max out your memory if you can.. I ran a 733mhz for 3 yrs..448mb ram and 64 mb video card and never had any problems with crashes..this site can help with some mods you can do to help
http://www.speedguide.net
do a google search for list of processes that run in xp...I use to have link but site is down right now..but speed guide is good place to start...Good luck