First thing I would do is return the dpw3925 for a dpc3010 telephone modem. The 3925 gateway is wireless n but not simultaneous dual band, old tech. The dpc3010 should be included at no additional monthly cost with your phone service, so you will save the monthly rental on the gateway. Add a wireless router like the tp-link C50 (under $50) & you have much better wireless. Depending on your budget & needs, you can upgrade you router from there, ASUS, Netgear Nighthawk & tp-link make some fine devices.
as for your question, what is happening that requires a reboot?
I had the same question when reading your post. What are your symptoms prior to rebooting your Gateway? The log shows multiple instances of WiFi interference. Is your Gateway sitting close to anything like a microwave oven, baby monitor, or cordless phone? We suggest a high shelf or other open area away from possible sources of interference. You can also try going into the router's management page and setting the wireless channel used to 1, 6, or 11 and comparing the results. That will particularly help if you have neighbors nearby that also have wireless routers.
AllenP offers some great suggestions, so please know that you do have options. While the Cisco DPQ3925 is fine for your subscribed tier of internet service, it is only an 8 x 4 single band device. If you have multiple users and multiple devices all connecting wirelessly at the same time, a dual band 802.11-AC WiFi modem might better suit your needs. I'd first make sure that you've eliminated all sources of RF interference. For more suggestions on how to improve your in-home WiFi network, go to http://bit.ly/ImproveHomeNetwork.
I rebooted Sunday 1/22 at 1pm. I rebooted today at 12 pm. I have moved my gateway twice. I have had to reboot at least 3 times a week. I was wondering if I should just go purchase a better modem and return the lease?
Since you are renting a Cox WiFi modem, my suggestion is that we schedule another service call so an on-site tech can verify signal levels to the Gateway, and swap the Gateway for another device if needed. I'm happy to schedule an appointment for you, if you like. Email my team at email@example.com with your full name, address, and a link to this page. If you'd prefer to swap the Gateway at a Cox Solutions Store before scheduling a service call, that's fine, too.