What makes the taskbar freeze but the rest of the screen work?

Since restarting Windows Explorer restores the taskbar, this points to the Windows desktop shell or something interacting with it, rather than the whole PC freezing.

Start by temporarily disabling any taskbar customisation tools or third-party Explorer extensions, if you use them. Test long enough to see whether the freezing returns.

If you don’t use those tools, try a clean boot: open msconfig, select Services, tick Hide all Microsoft services, then disable the remaining services and disable startup apps in Task Manager. Keep track of what you changed. If the problem stops, re-enable items in groups to identify the cause, then restore the others.

Also search Start for View reliability history and check the times when the taskbar froze. A Windows Explorer failure entry may identify a faulty module.

Restarting Explorer is a reasonable temporary workaround. A lasting fix depends on identifying the trigger; this symptom alone doesn’t justify reinstalling Windows.