Windows 7 - Delete the partition or format during clean install?

Once you get to the Custom (Advanced) tab of Windows 7 clean install there are options to delete the partition, format, etc. Assuming I want to delete all of my partitions so that I have one large volume C: is it best to delete the partitions first and then format? Why would someone do one over the other (or both?) Right now I have a C: partition and a D:RECOVERY partition. I want to delete the D: partition and combine it to the C: partition.

Don't they do the same thing? Why do you need to format after you delete a partition ? Do I also delete the C: partition and "re-create" it? What about the term "Unallocated Space"

I apologize if these are easy questions but I feel this is the most important step of my clean install.. I plan on doing this once I boot from the Windows 7 DVD.

Unallocated space is the easiest one. It is space on the HDD that is not part of any partition. Simple enough to understand. When you format a partition, you erase everything on that one partition, and set it up to be written to (leaving it as a partition), while leaving other partitions untouched. If you delete a partition, everything on it will be erased and it will become unallocated space, which will need to be formatted before written to. For what you want to do, you will need to delete both partitions. When you delete more than one partition, it becomes a big hunk of unallocated space. You can then make as many partitions from that unallocated space as you wish. If you merely reformat, without deleting the partitions, you end up with the same two partitions you had before, with the exact same size. Any other questions?

Delete both partitions, create New of the size you want, format and install.

Installer will create a 100mb System Reserved boot partition which places the boot files outside the OS and also places the Windows 7 Repair console on Advanced boot tools accessed by tapping F8 at bootup. This is no problem at all and can be ignored.

You might want to make the Recovery disk set if you haven't already before deleting the Recovery partition, so you have a path back to Vista/XP if you should want to sell the computer but keep your Windows 7, or need to ship it back for warranty servicing.

OK I think I've got it ..

Step 1) Delete both partitions C: and D:
Step 2) Format the large partition (which is now "unallocated space" ?)
Step 3) Click "Next" and Install Windows 7 on the large partition that I just formatted

Am I missing a step where I have to make a "New" partition? I only want one partition C:

Could you tell me if this is correct?

Seems like you got everything figured out. Formatting will make the new C: partition for you. I hope you enjoy your experience with Windows 7. We are always here to provide any assistance you need in the future.

The format step is actually unnecessary. If you try to install 7 to an unformatted partition, it will be formatted in the process anyway.

^^ What MacGyvr said ^^

Yep, this is the case. In fact, I always blank my drives first, before even booting from the Windows 7 DVD. There's no real reason to do so, though, if you plan to install the same OS on the drive again.