Hi Dan,
In addition, you may change your wireless channel to 6 or other channels and see if it will make a big difference.
-Try a wired connection as well to see if the wireless is your only issue.
-Boot to Safe Mode with Networking by restarting your computer, tap F8 then select this option and see if you're able to replicate your issue.
-Refreshing your wireless profiles by deleting them, then re-add you own SSID(wireless network) might also help.
How to remove the existing wireless network profile in Windows 7 - Welcome to TP-LINK
- Update your Intel Wi-Fi driver to the current one.
Intel® Driver Update Utility
- Disable your Norton temporarily if above suggestions didn't help.
An update will be appreciated.