hi,
I guess you are using standalone Symantec Encryption Desktop. I would recommend this for backup purposes:
1. Backup your keyring and keep it in a safe place. You can export them as *.asc file (remember to check the "Include Private Key(s)" while importing). You are using them for email, File Share encryption.
2. Create WinPE for a Disaster Recovery situation (like you are not able to boot the machine) - see https://support.symantec.com/en_US/article.HOWTO95227.html
If crash of the system happens, you can access the machine booting from WinPE and access the data (eg. you can decrypt them). You can refer to this: http://www.symantec.com/connect/articles/how-decrypt-drive-windows-pe-symantec-encryption-desktop-10x
3. Once you start encryption of the disk, the Whole Disk Recovery Token (WDRT) appears on the screen. Keep this number in a safe place (not this machine). It will not reappear again.
4. Remember the passphrase for your drive encryption. Do not store it in a clear text as this is not secure.
5. If data is critical, ensure to implement backup solution of the data.
6. Run test of disaster recovery in lab to ensure you are familiar with the recovery.
7. Periodically check if you are able to restore data from backup