How do I further decrease the width of small, pinned icons?

Solution 1:

This will show you how to customize how wide you want your pinned taskbar icons.

How to Change the Windows 7 Taskbar Icon Width Size

Set the options

1. Open Taskbar properties.
2. In the "Taskbar Appearance" group, change the "Taskbar Button" option to your liking. Select "Combine if full" if you still want stacking, "Never combine" if you don't want stacking. Note this hack won't work if you use "Always combine, hide labels".

Adding/editing the registry entry

1. Press Windows Key + R to open the run command
2. Type int "regedit" (without quotes) and press OK
3. Go to HKEY_CURRENT_USER -> Control Panel -> Desktop -> WindowMetrics
4. Find the "MinWidth" entry.
5. If it is not there, right click on an empty space and select New -> String Value. Name this entry "MinWidth" (without quotes)
6. Double click on the MinWidth entry. If you want just the buttons to show, set this to 38 if you're using small buttons, 52 if you're using large buttons. Otherwise any value above 38 will work. If you set a value below 38, the buttons will behave oddly.
7. Log off and log back in or restart to see the changes.

Deleting/Uninstalling

1. Press Windows Key + R to open the run command
2. Type int "regedit" (without quotes) and press OK
3. Go to HKEY_CURRENT_USER -> Control Panel -> Desktop -> WindowMetrics
4. Find the "MinWidth" entry and delete it.
5. Log off and log back in or restart to see the changes.

Source and registry install script for small or large icons and an uninstaller

Solution 2:

No, won't work. It only affects the behaviour of active icons, not the inactive ones. My advice: create a new toolbar (e.g. quickstart) and put your desired icons on that and loose the pinned icons.