The clue was in the question - AOL !!
Yes, by all means upgrade your firmware but be very wary that there are some later versions of firmware, specifically for the DG834, which will not allow a login to the dreadful AOL software. Not a problem if, like most sensible people, don't use the AOL s/w.
You may already be aware that AOL have over the past months been migrating users from their own network on to the Carphone Warehouse network.
This has caused dramatic speed decreases for many AOL customers. You may have noticed your WAN IP address changing to a 92.x.x.x address.
Post your Netgear router model and I can hopefully advise a little further.