You will probably find that the "cannot connect to dhcp server" issue is because you have an old or other wireless connections in your system. Perhaps it is a work and home laptop or the like? I wouldn't worry about it. If you are typing here, the right connection was made.

The other event viewer stuff doesn't really apply.
If you are having latency issues you have to determine where it is. One spot, all spots. etc. A place to start for that is a simple tracert. You go to command prompt , type "tracert tweaking.com > trace.txt " (not quotes. This will create a text file call trace.txt that you can upload here. You are looking for things with large hop times. If the large hop is your router - well, there's the issue.

the firmware update on the router is a solid idea.
if you want to disable LSO, I believe you do that from the network adaptor, not router. Click start> control panel > change the view to small icons. Then look for network and sharing center. Click change adapter settings. Double click the Local Area Connection and click properties then configure. Click the advanced tab. Find large send offload for IPv6 and IPv4 . Disable then and reboot.