Whatever you do, don't store it in gmail or dropbox or cloud.
why not?
Because those services exist to share files and are not secure. Hackers can take their sweet time trying to break into your gmail or drop box account to steal your wallet. Then they only need to bruteforce your password.
OTOH, if your wallet only exists on your PC, and perhaps a backup on a removable drive, then the hacker has to target your personally. Last I checked home PCs did not usually serve files to the general public so there are fewer avenues for attack.