I have had a standard Internet setup in my home network for many years and my router is set to 2.4 ghz but I just recently got a new microwave and every time I use it the Internet seems to kick out only the laptops near by. If I change the frequency to 5 ghz all my computers except the newer ones will kick out because their network adapters only support 2.4 ghz. I am tired of dragging an either net cable through my house and I was wondering it there was a possible fix to this?
Well, microwaves are the reason why 2.4GHz frequency is not licensed.
This is because first microwaves were using 2.4 GHz and it was basically impossible to regulate, this frequency was left open.
Later on, a lot of other devices started using the same frequency: 802.11b, Bluetooth, later 802.11g, then cordless phones, these days 802.11n, etc...
Of course, this led to the tragedy of the commons - one common frequency is getting abused by everybody. Using new 5 GHz frequency helps a bit, but way too many devices depend on 2.4GHz being available.
Regarding your particular microwave - it is possible that you can get better shielding by replacing it, but you cannot possibly reduce this effect to 0. Also, there is no guarantee that your neighbours' microwave will have perfect shielding either.