One easy thing to try is to de-activate your plug-in Coupons, Inc. Coupon Printer 5.0.0.2 . Is it on both computers? I'm not saying anything against it but it is a bit of a stand-out in your System Details shown above. Google it for more information.

I have deactived the Coupons Inc plugin and it is only installed on my PC which is Windows 8.1 but that doesn't help

We're sorry to hear that Firefox is crashing. In order to assist you better, please follow the steps below to provide us crash IDs to help us learn more about your crash.

1. Enter about:crashes in the Firefox address bar and press Enter. A Submitted Crash Reports list will appear, similar to the one shown below.
2. Copy the 5 most recent Report IDs that start with bp- and then go back to your forum question and paste that into the "Post a Reply" box.

Thank you for your help!

More information and further troubleshooting steps can be found in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

Hi Tyler I have attached a screenshot of 5 most recent reports but what is the cause of the crashing on two computers using the latest version of firefox but on two different Windows Operating Sysytems

I asked you to copy and paste the reports not a screenshot. Please follow the directions above exactly

Hi Sorry I though you meant a screenshot of them not the reports itself.

https://crash-stats.mozilla.com/report/index/bp-9687aafb-1531-4024-a799-2ecf42140703 https://crash-stats.mozilla.com/report/index/bp-3d02ec48-b8a3-49e8-9a89-39fbd2140702 https://crash-stats.mozilla.com/report/index/bp-40729b09-518c-40b0-8198-2b78e2140701 https://crash-stats.mozilla.com/report/index/bp-d6aa02c5-0998-48c9-9561-a4dab2140630 https://crash-stats.mozilla.com/report/index/bp-47903a98-ecda-4107-b636-58dde2140629

That crash is caused by Norton. Remove your Norton Toolbar (It's useless anyway) and update your Norton Anti-virus. If you still have a crash please let me know.