Here is an old trick carried over from Vista. I have been using Vista for quite long time but to be honest, I never knew that. Often, in Windows Explorer, if we want to see the larger icons as bigger thumbnail we just choose one of the four pre-defined size of icons, Extra large, Large, Medium, or Small, from the view option. Now, you can actually do that a lot quicker. Just hold down the Ctrl key and scroll your mouse wheel in any folder, the icons in that folder immediately resize bigger or smaller. What’s even better, it actually can switch between the other view options, e.g. List, Detail, etc. Give it a try. Credit goes to The How-To Geek on Resize Icons Quickly in Windows 7 or Vista Explorer
How can I resize the user account profile icons on the Windows 7 logon screen? They are TINY! Thanks.