Thanks for all the feedback again!
But since it was the weekend and I hadn't returned my Netgear D834G yet, I thought I would try at getting it to work again. After hours of tinkering with rules, settings and resetting the router, I still couldn't get it to work then the culprit showed itself...
It was a
HIDDEN process of my previous Outpost Firewall!! I thought it was turned off but it wasn't and was running hidden away from Task Manager! I wouldn't have found it if it didn't happen to crash itself today. Man, I've been going in circles because of it
I've uninstalled the thing and now my Netgear wireless/router/firewall/modem works flawlessly again
I installed Zone Alarm Ad-Aware version instead since I still need to open ports for BT and stop programs accessing the net. Would have preferred Outpost because it shows what connections are active and rules are a lot more tweakable on the spot but, oh well.