A:
1): Use Hiran boot disc or similar disc, and then run Partition Magician, set the recovery partition as the primary one, and then you could enter it. There’s no specified requirement for which disc you should use, but this would help you change the primary partition, yes, that’s right, it could preserve everything, I used when I repaired my customers’ laptops, and it’s just a autotype process.

2): When you start it, remember to set boot from disc 1, then in Hiran disc, choose the partition tool and then use partition magician.
 And then just choose recover the partition, right click it, set it primary partition, then it would force drive C not to start until you set it primary partition again…
You could boot the disc on recovery partition. And then do whatever you