I am using D-Link DWL-G700AP connected to Motorola

This problem occurs because of DHCP issue in router.
Your computer not get proper ip for connect network.
For that first reset router to defaults.
Press RESET button for 10 seconds it is in back side of router.
Then connect router to computer with ethernet cable.
Then you can access it with following link.
http://192.168.1.1
or
http://192.168.0.1
type user as "admin" and password as "admin" or blank or "password"
then you can see configuration of your router.
Set WAN settings as your internet service provider settings.
Enable DHCP in advanced.
click on wireless or wi fi menu and enable wi fi .
Enable WEP or WAP security if you want to secure then add key it is your password to connect internet.
Then save and restart router then check.
Let me know if you need more assistance.