Yellow lights in Network Diagnostics constantly

[AppleTech22]

As I am browsing the internet with good speeds, sometimes my connection just "stops". The blue bar in Safari just sticks at about 1/2" and doesn't move at all. I then solve the problem one of two ways: By quitting in and out of Safari multiple times until it works, or going into Network Diagnostics and going through clicking continue until it works. I have tried restarting(turning on/off) all three of the "pieces" involved in my home network, which are:
-The older Apple Airport Extreme(for my iPad, iPhone, ps3, computer, and brothers xbox)--Not all on at the same time
-The D-Link EBR-2310 wired router that spits out 3 connections, one to my dad's office, one to the computer in the loft, and one to the Airport.
-Then the ancient source which is the Motorola SB4200 SURFboard Cable Modem. I don't even remember when or if we ever had another router(I'm only 16). Using Time Warner Cable.

Anyway I have no idea what I am doing with networking really, and not sure what the problem is. There are the pics down below of the 3 devices and network listing. Any help is very appreciated and I will be quick to respond to any questions.

 

[mainstay]

the AEBS has DHCP turned off, correct?

do you ever get this issue if you connect directly to the surfboard modem via cable?

what are the lights doing on the surfboard when the issue occurs?

have you update the firmware on the dlink?

have you confirmed with your ISP that their is not a service disruption?

how often does this occur?

can time warner replace the modem with a free replacement?

which method are you using to connect to the internet (wired or wireless?)... are you the computer in the loft or the computer via AEBS?

anyone else on the network having issues?