Change DirectoryRoot to <Directory c:/wamp/www>
Make sure the ownership and permissions of C:\wamp\www
User: yourusername
Permission: Allow - Read and execute and Read permissions
you should try this:
Edit C:\wamp\bin\apache\apache2.4.9\conf\extra\httpd-vhosts.conf (apache2.4.9 might be different, depends on your apache version)
Scroll all the way down until you find Deny from all and change that too Allow from all
EDIT Answer to @Bonner
Your permissions are still wrong
If they still wrong, please provide the right permission, instead of just point it out. Based on "my poor knowledge" I think the permission are fine.
you have failed to ask whether the WAMP tray icon is appearing or not
Based on question description
After restarting my WAMP server,
I assumed WAMP tray appears.
If you make changes to the httpd-vhosts.conf they will be overwritten by the tray icon software when an option is changed
False. WAMP Control Panel let you edit configuration files like my.ini, httpd.conf, php.ini, etc. However, you can't edit httpd-vhosts.conf from WAMP Control Panel.