Wireless computer gets changed and denied web access??

I’ve been having this problem quite some time but never did anything about it since the problem will go away after several reboots and several resets of the wireless router. But I want to know the cause of this.

The problem I get is I have a computer that has a NetGear wireless card that gets connected to a NetGear wireless router. Whenever I boot up my system I get an IP within 192.168.1.2 to 192.168.1.77 Sometimes when I boot up I would get an IP outside my allowed range for example I would get 192.168.8.16

When that happens I can’t get access to my internet. Does anyone know how to prevent my wirless card or router from issuing an IP outside range of the allowable internal IPs.

Thanks in advance!