I am assuming you want to get rid of Vista which is on C, and keep Windows 7 which is on G. Is this correct?
Do you want to keep your Recovery Drive so that you can run it should you ever want to restore Vista to factory condition?
If Dell provided a Vista install DVD you have the ability to do a clean install without the factory bloatware so consider if keeping the Recovery Drive is worth it since it will most likely not run now that it has been crammed with backups.
If you don't mind getting rid of it, then we can give you the steps to do this, recovering the hard drive space into either of your partitions. You can even set up a separate data partition so your files are kept separate from the OS but linked to your User folders and Libraries.
If you want to keep it, then please post back a screenshot of the contents of your Recovery Drive showing all of the folders at once if possible. We can help you figure out which are the backups that can be deleted, then you can make sure never again to allow anything to be downloaded or saved to that drive letter.
Please also post back a screenshot of your full DIsk Management drive map so we can see the drive configuration.