Here are the steps to get back the small taskbar when docking on the side:
1. Right click on the taskbar and select properties
2. Make sure Lock the taskbar, Auto-hide the taskbar, Use small icons are all checked
3. Click Ok
4. Press Windows Key and type services
5. Restart the "Desktop Window Manager Session Manager" service by right clicking on the service and select Restarst
6. Unhide your taskbar and select Properties
7. Uncheck Auto-hide the taskbar
8. Sit back and enjoy the smaller taskbar
Here is a video that goes through the steps.