I am trying to grow my C: drive to use the unallocated space on Disk 0.
Is it safe to throw away the Recovery Partition (i.e. make it unallocated)? And if so, is GParted an ok tool to do that with?
And after I delete it, if I leave enough unallocated space after joining pertitions, is there a way to have it build a new recovery partition?

C:partition, asC:doesn't requre >300GB if storing user data directories on a separate partition (most efficient). Before deleting the WinRE partition, mount it viadiskpartand copy theWinRE.wimout of it (it's more convenient than pulling it from a Windows ISO). Once done, remove the mount point, delete the partition, expandC:, then recreate the WinRE partition (I recommend placing WinRE in front of the system partition [C:], else the partition order becomes an inconvenience, esp if using an SSD). – JW0914 Jan 30 '21 at 15:59