Who dual boots Windows * with some sort of Linux

[leapFrog]

You don't start your laptop using BIOS or UEFI; you start your operating system.

If you have installed Windows using UEFI then you can then install Linux with rEFInd, using the Windows EFI partition.

[petergriffin]

Ping Sysman

Do not try to use Gparted on NTFS boot partitions. As of a year or 18 months ago it didn't understand NTFS disk geometry properly and a subsequent boot would result in some pretty lengthy CHKDSK runs. Shrink it as far as it will go from within Windows. To shrink further you will need to mount it as a non-system disk in another instance of Windows or buy other software which is designed to deal with NTFS in its latest incarnation.

I was set for shrinking natively in Windows with Administrative Tools --> Disk Management tool -> Shrink Volume, when I read this:
https://help.ubuntu.com/community/Ho...ons#Defragging

If you are planning to use GParted, you can skip defragging and save yourself some time, because GParted can resize an NTFS partition safely regardless of its state of fragmentation.

and:

GParted Partition Editor

If you decide to use GParted, you have to remember to uncheck the 'round to cylinders' checkbox , otherwise GParted will dutifully move the entire partition to align it with cylinder boundaries. Unfortunately this takes a long time, and when it's finished, usually results in booting problems. This is because the Windows boot loader depends on block addressing to find parts of itself, so when the partition is moved a little, it gets all mixed up and disjointed. Sometimes it can fix itself automatically but other times it requires repairs from the Windows Installation Disc. If you just remove the check mark you will find that GParted will be able to complete the NTFS resize in a fraction of the time it would have taken otherwise and afterwards Windows will boot just fine.

Is it possible that you forgot to uncheck that option? And did you manage to rescue the partition?