ABOU,
The IP address lease time is controlled by your router, not your PC. Some routers let you reserve DHCP IP addresses based on the PC's MAC address. This allows you to keep using DHCP, but permanently assign an address based on your PCs physical network address.
The other option would be to assign STATIC or manual IP addresses on your PC rather than having the PCs lease their addresses from the router.
http://www.tech-faq.com/how-do-i-set...-windows.shtml
For more information about configuring your router, go to:
www.linksys.com
- John