When multiple instances of a program are running (but windows are closed) in Windows 7, is there a way to have the program open by clicking the taskbar button (without having to take the extra step of clicking a thumbnail)?

Right click on the taskbar. Click properties, you should see something that says “Taskbar buttons”. You can choose to have it “Never combine” or to only combine when full.
This would make it handle windows the same way vista did.

That’s a good question. I don’t see any way. I’ve noticed, though, that with the introduction of Vista, Microsoft is all about adding extra steps to do simple things. Like changing the time and date.

I like to use the WindowsKey + Number to do this type of thing. If your internet explorer is the 3rd program on the task bar, selecting WindowsKey + 3 will bring the 1st opened window to focus.

Selecting WindowsKey + Ctrl + 3 would bring the last viewed window of internet explorer to focus.

Also this works if you have the program pinned to the task bar but not opened it will launch the program.