Random High Ping

Within a week or so ago, I started having trouble with playing online games. The games would seem to disconnect from the internet for only 1-2 seconds and then resume playing. After messing around with settings, I went on to find out that my entire computer was having this issue on other games and online activities, timing out only for a few seconds and then resuming. After doing a bit of research, I was told to constantly ping google.com (ping google.com -t). My network was steady around 20-40 ping and was fairly normal but was occasionally jumping to well over 100 and sometimes all the way up to 500. Sometimes it even timed out the ping request. I knew that their were three possible answers. 1. Software on my computer was causing this. 2. The Airport Extreme router itself was causing this. Or 3. My internet was causing this. First thing I did was to test on another computer and it showed the same results, eliminating #1. The second thing was to test on a computer connected by an ethernet cable, which did not show the same results and showed normal ping consistently, eliminating #3. I then tried to power cycle the router which failed and then tried to reset the router which also failed to fix the problem. The router is only 1 1/2- 2 years old and hasn't given me any problems until now. If I turn off all port forwarding options, the time between the spikes is longer.

My main questions are:

1. Is the router going bad? Do I need to replace it?

2. Is there another solution to this problem?

3. Is something wrong with the software? Should I try using an older version?

Any help is very much appreciated!