According to the Gparted map, you have three (3) “unallocated space” areas. One (66.16GB) is already within your extended partition, and available for assignment. The small (7.48Mib) area at the physical end of the volume is clandestinely used by Windows and the NTFS file system. The actual amount used is less than the 7.48MB. I suggest that you leave this small area alone. You might open the door for both Windows and volume recovery.
The largest unallocated area (97.66GB) is completely unassigned. You may allocate a primary partition there, or add it to the existing extended partition.
CAVEAT: Make a backup!!! Should you not have a working, restoreable backup, all the magic available cannot rescue a misstep!
To augment your extended partition, it must not be in use: i.e. you must perform the extension from a liveCD that contains a partitioning tool such as the Gparted you have used. (Gparted indicates a partition in use with a key/lock icon).
Boot the liveCD and click on the extended partition (/dev/sdb3). You should see the option to “resize”. (If this option is greyed out, the extended partition is in use).
The partitioning tool will show you the amount of space in use, available in front, and available at the end. Adjust your allocations as desired.
Remember to leave that 7.48MiB area alone !
If you are unsure of these steps, you can perform everything but the actual resize, and take screen captures to post here. I would rather see each of your steps before you attempt to resize, as opposed to trying to recover problem.
Yes you can expand the extended partition to the left. But you should be warned about a couple things first:
don’t do it from your running system. Use an Ubuntu live CD (because it has gparted installed) or PartedMagic.
Before doing that, edit your /etc/fstab and replace whatever syntax it uses with UUIDs, meaning NO device names and NO /dev/disk/by-id (openSUSE’s default). Mounting either by labels or by UUID is the only method which will survive a change in partition numbers (which is going to happen as soon as you create a new logical partition). I posted many examples of mounting by UUIDs in the french subforum.
If you intend to add only one partition, you don’t need to expand the extended partition. Just create a primary partition in the unallocated space. (in that case your /etc/fstab should still be fine).
DON’T move sdb5 and sdb6 within the extended partition, before or after resizing it … although it is possible, but better don’t do it!
Be warned that your Linux system is NOT going to boot anymore. So after resizing the extended partition or creating a new primary in the unallocated space, you’ll have to reinstall GRUB (and first edit /boot/grub/menu.lst accordingly).
I say it again: be prepared to reinstall GRUB in order to be able to boot Linux. You’ll find how in many posts and faqs on this forum.