When the brain engages i have to type quickly or it gets too far ahead,minimal punctuation allows me to keep up ,well that's my excuse
Yes & sort of
D = i assume is the recovery partition this needs imaging only once by itself or as below along with C;however i like to make a separate image of D,then do the following in the next paragraph:=
C = i normally create a partition image directly after a reinstall & include the D partition if there is one;once done all future C images are system images of C only; using medium compression level.
The term system image maybe different if not using easeus,it's nothing more than the data only of partition C
Once the above have been created on multiple externals you can pick differing intervals for future images to be made;i personally make 4-5 more initial images (never to be deleted) at varying stages usually just before adding a few more 3rd party software's & windows updates (in other words add some 3rd party apps & some windows updates but not all at once).
After the 5th initial image is created or the last one; which is when all windows updates are installed & all 3rd party software;you can then setup a auto imaging scheme,which is used to create images that can be discarded as space is required;obviously older images get deleted as new ones are created.
Ok now down to the hard drives:-your most probably wondering why i said more than 2; it's because you can loose data on both at anytime & at the same time,yep personal experience taught me that;in the end it comes down to, "how much is that data worth to you " & "can you afford to loose that data",how many posts or news articles have you seen where someone has lost personal data from a failed hdd (hard drive) or had family photo's stolen,if they had multiple backups it wouldn't be an issue;so those multiple hdd's serve two purposes,they house your backup images as well as any other stuff you want to keep by drag n drop.
All images created can be browsed as tho it was a folder once the image is mounted simply by right clicking & selecting open;so long as the program that crated them is still installed or you have the boot disk (recovery disc) of the imaging program;basically it's a bootable cd of the imaging program
edit:above i mention drag n drop this is for loose folders or files NEVER EVER DRAG N DROP IMAGES as corruption may & can occur;yep happened to me;another thing to keep in mind is the only real way to test an image to make sure it will work is to use it to restore;it's also the reason i create all images independently on all externals coz if you drag n drop you may transfer an already buggered/corrupted image
edit 2:below is a link if you require specialist help with imaging,it's a place called Radified Community Forum they do nothing but talk imaging & has been around a while