Your WAP may be on it's way out. I had a similar situation with a Linksys WAP54G (I think that was the model) and a Buffalo router my wife had when we were dating. The Linksys WAP thankfully died, and I replaced the Buffalo router with a WRT54GL running the tomato firmware which coped with her apartment better. That it fails on heavy, sustained downloads suggests the WAP may be the problem.
Does your Verizon FiOS box not have wireless capability? Have you check for WAP firmware updates?
1) Uninstall the buggy Netgear drivers.
2) Go to a some place like Panera or Starbucks that has Wifi access, and see if the problem follows the computer equipment.
3) Go to a friends house and see if the problem follows the adapter.
4) Bring the friend back to your place, and see if he has the same problem.
5) Analyze the data, and make decisions based on that.
It still only connects at 72Mbps (and it's slower than that most of the time), while my AP is supposed to support 150Mbps. (the netgear adapter claims 300) It seems like my AP is not using the 5Ghz band so maybe 72Mbps is the best I can get.
72Mbps is really good. Yeah, you're not going to see the 150 Mbps. That speed is theoretical at worst or achieved in a perfect environment which doesn't exist outside of a lab with no packet overhead at best.
Edit: The WAP has a 10/100 Ethernet connect which will also bottleneck you if you're measuring speed to a machine connected via a wire.