I have an ASUS M51AC tower with one hard drive. It has seven partitions, one being for data. I'd like to get rid of the data partition as I put everything on a NAS drive. Which partition(s) can I get rid of and consolidate them to C:? The partitions are (from left to right in Disk Management):

#1 - 800 MB Healthy (Recovery Partition
#2 -260 MB Healthy (EFI System Partition)
#3 -874.23 GB Windows (C:) Healthy (Primary partition)
#4 -499 MB NTFS Healthy (primary partition)
#5 -350 MB NTFS Healthy (primary partition)
#6 -34.20 GB (D:) Healthy (primary partition)
#7 -21.14 GB Healthy (Recovery partition)

I already shrank the D: partition and added it to C:. I'm guessing the last partition, #7 21.14 GB, is for the ASUS factory restore.

Would I mess up anything if I got rid of D: altogether and added it to C:? How about the two middle partitions, #4 and #5? Can they also go away safely?

Thank you,
Brian