All the bitcoin address you generate in internet may not be ideal for storage of bitcoin for longer term if the amount is so much.
You better download https://github.com/pointbiz/bitaddress.org and store it in any folder in a new computer without any online connection or USB stick attach (better to use just formatted pc/laptop). Than open bitaddress.org.html file in browser and generate bitcoin address, no any internet is needed. Save that or print that paper wallet you get. And only copy that bitcoin address to one plain text and delete that paper wallet file .pdf you get from the script. Now only insert USB disk where you have to copy the plain text file with btc address you created before.

Than use that address to send bitcoin to it, i think this is the good way to store bitcoin for long term and most secure cold storage paper wallet method exist. Correct me if there will be a chance of lossing private key in the above method, i am also also thinking to store for long term with the above method.