when i open any web page, it is closed immediately saying that windows explorer encountered some problem and
some times i am getting a message .. virtual memory is running low

operating system is windows xp
ie version 6.0

could u tell me why is this happening

regards
sitaram

Too many programs running in the background (system tray) can cause this. Chat clients, Messenger programs ect.
Too many programs running in the background you don't know about Malware, Trojans, Spyware, Adware also can cause this.
If this only happens when your browser is open (and a lot of HD activity) you may have a worm.

http://www.experts-exchange.com/Operating_Systems/WinXP/Q_21038913.html
http://www.experts-exchange.com/Operating_Systems/WinXP/Q_21151441.html
http://forums.techguy.org/archive/index.php/t-257977.html

Ad-Aware SE Personal Edition
http://www.download.com/3000-2144-10045910.html

HouseCall
http://housecall.trendmicro.com/housecall/start_corp.asp

PestPatrol
www.pestpatrol.com/

Firewalls;
http://smb.sygate.com/products/spf_standard.htm
www.zonelabs.com