Dual Boot method

Solution
You have better control of partitioning with Partition Managers... you can use the mouse to visually resize and create partitions.. and you can preview tasks and if necessary make corrections before actually executing them. With the Windows Disk Manager you only have one chance to do it right.

I'd suggest MiniTool Partition Wizard Home Edition... it's apparently everyone's favorite.
http://www.techsupportalert.com/best-free-partition-management-software.htm
Linux should create it's own dual Boot...
Windows versions from Vista to 8.1 should create the dual boot, and in case it doesn't as the earlier version should be installed first to make sure dual boot issues don't happen, EasyBCD should easily help solve it.

You can use EasyBCD Community Edition (freeware) installed on the newly installed Windows... as it is the only one to boot when such issues happen, and later when you can boot Windows 10, you should install EasyBCD on it and edit it's bootloader the same as on the new Windows installation, and make Windows 10 the Default OS.

EasyBCD Community Edition
http://www.softpedia.com/get/System/OS-Enhancements/EasyBCD.shtml

Configure a multiboot with EasyBCD
http://ccm.net/faq/26380-configure-a-multiboot-with-easybcd
 
You have better control of partitioning with Partition Managers... you can use the mouse to visually resize and create partitions.. and you can preview tasks and if necessary make corrections before actually executing them. With the Windows Disk Manager you only have one chance to do it right.

I'd suggest MiniTool Partition Wizard Home Edition... it's apparently everyone's favorite.
http://www.techsupportalert.com/best-free-partition-management-software.htm
 
Solution