Wireless networking problem - Error 12007

For the last 2 months been getting dropped from my connection. Using a
wireless network and having to constantly use the diagnostic tool to
re-connect. Getting a 12007 error quite a lot..

I've done ipconfig /all (as suggested by Jack(MVP-networking) ) and I still
have a local IP address attached to my machine.. he suggested that if I have
an address then its a problem between my router and modem. The windows
toolbar still says I'm connected to my network when I lose the connection...
so is it a problem between router and modem???

If this is definately the case, what do I look for and how do I fix the
issues between my router and modem?? This only started happening a few months
ago and can't figure out why. Is there any other reason why this could be
happening??

Should I call my ISP and see if its a problem from their end??

any help would be greatly appreciated!!!