Sorry, a stupid question, is your copy of FSX legal. Not trying to get you into any hot water, but trying to find where you problem lies. Illegal versions are cracked and tend to do this, as you are experiencing. "Some" crackers have good code and one cannot tell anything from the original, but most write bad code, to kludge past the protection, and cause major instability.
If this is not the case, then do you have a separate hard drive spare. You can then just install your O/S with the latest drivers, and FSX on this drive, disconnecting all others. Don't install any malware protection, such as you mentioned Norton security. You will quickly see if it is your hardware or current installation/setup etc. causing the lock up. This seems to be coming from FSX, as you are running other high end games with no problems.
What you can also do is completely uninstall FSX and any and all entries lying under the user folders (your user name folder - appdata - local and roaming) Program files (x86) and Programdata folders. You might need to "unhide" these folder, using the folder settings. Thereafter use a good, and I mean a good registry cleaner, my recommendation, Macecraft's JV16 Powertools, the best AFAIAC, having used it for the last 10 years or more, to clean up your registry, and search for anything named FSX, and delete it. Why do I say a good registry cleaner, firstly you are running RAID 0, no redundancy, and a failure on this is catastrophic, no user recovery at all, and slim to none from a professional service. So if in doubt backup all of your user data, documents, music, pictures and emails etc. Secondly there is absolute crap out there in registry programs, that certainly do as they advertise, of doing a good job of cleaning your registry, by simply deleting the entire hive, so be warned "there be dragons within".
Then run a defrag of your system, reboot and re-install. Run every install completion of FSX, at least up to the selection menu, and set your required settings, before applying the next or a new patch or fix, to set the configuration. Don't be impatient.
This always works for me, and I have a similiar hardware setup to you. And one other thing, this normally affects FSX on start-up, as a known issue, but it might just be different for you, find your logbook in C:\Users\<accountname>\Documents\Flight Simulator X Files\logbook.bin, rename it, and try FSX again. The known problem with this is that the logbook can and does become corrupt for various reasons, and hangs FSX. If this does work for you, then there is a logbook editor available for free that can fix a corrupt logbook and save your previous entries. You generally only lose the last entry. Hopefully from this advice you should get all working again.
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