Consumer electronic devices do not have an expiration date. "Seven years" has no basis in fact. Most equipement will last for many years operated in a typical home environment. I've had plenty of gear that has lasted for decades.
While old, the Actiontec Rev I. was a decent router. I routinely got over 100Mbps on 802.11n with mine. In fact, I was recently running it as an AP in my basement and got good speed out of.
Do make sure it's updated with the latest firmware, as older versions didn't have WPA and that's a security risk. You'll have to plug it into a Frontier network to get upgraded.
Switching to performance mode is important to getting higher speeds. The other thing you can do is check if the assigned channel is congested. If it is, WiFi will slow down. The best channels to try are 1, 6 and 11. If you can get a WiFI analyzer going, that will give you good guidance.
You should also check if the WiFi adapter has any relevant settings and that she's using the latest driver.
If your friend isn't on Verizon FiOS, a new router is an easy solution. Many aren't terribly expensive. If she is on FiOS, she may need a Verizon router depending on if she has Verizon TV service and/or if she cares about getting support from Verizon.