You installed grub2's boot loader to the PBR - partition boot sector of sdb2 which is your Windows boot partition. NTFS partitions have essential Windows boot code in them and you cannot install anything else into any NTFS PBR, even data only.
Fix for most, a few have other issues, better than windows fix in many cases as it also fixes other parameters:
File system: ntfs
Boot sector type: Grub2 (v1.99-2.00)
Boot sector info: Grub2 (v2.00) is installed in the boot sector of sdb2
and looks at sector 1758363544 of the same hard drive
for core.img. core.img is at this location and looks
in partition 1 for (,msdos5)/boot/grub. No errors
found in the Boot Parameter Block.
Boot files: /bootmgr /Boot/BCD
If win7 use small 'system reserved' NTFS partition instead of the partition where windows was installed for win7
This has instructions on using testdisk to repair the install of grub to the boot sector for windows from Ubuntu or Linux LiveCD.
You want to get to this screen:
[HowTo] Repair the bootsector of a Windows partition - YannBuntu