EXTREMELY SLOW ICS CONNECTION

Hello everybody. I use an ICS connection @ work but have been racking my brains trying to figure out what went wrong the connection thoughout today seeing all the systems though can get a DHCP address can’t open web pages save for google which is the start up page[the ICS server is connecting and opening different web pages]. Must add that the ICS has been fine for like 3 weeks now. Any insights?

IP Addressing Scheme- 192.168.0.1-192.168.0.255…..System on which ICS resides uses 192.168.0.1 with .255 been the broadcast address.
No servers. ICS running off a Windows XP sp2 system
Other Client systems run XP sp2