Why did my taskbar just change it's color???

[???]

It was black. Always has been for the longest time. About a couple minutes ago, it turned sky blue. While it was changed, I was on a chat site and when I would type, each letter would show up a few seconds late. Then a minute later it went back to black and the typing isn't lagging anymore. Did someone hack into my computer??

[Akashi Seijūrō]

Nope, no one has hacked into your computer.

"I was on a chat site and when I would type, each letter would show up a few seconds late."

Slow reactions by computers are usually caused by the CPU being used up by some software running in the background. It could also be caused by the lack of physical memory (RAM).

If you meant Sky Blue Window Color as in this image: http://res1.windows.microsoft.com/resbox...384_78.jpg

Then there's nothing to worry about. It was probably "Winsat.exe" running in the background. It's a Windows Assessment Tool by Microsoft. It runs a couple of tests to benchmark your computer. Hence it eats a lot of CPU and other stuff lags for a moment. If it happens to you again, then go to Task Manager (Ctrl+Alt+Delete) > Processes > Find Winsat.exe > Right Mouse Button > End Processes should kill it immediately, and you should switch back to your Windows Aero Theme.

You can also prevent Winsat.exe from running again, but I don't think it's necessary. Just kill the process when it starts benchmarking if you don't want it to run.

If you're curious as to where your benchmark scores are, then Right Mouse Button on Computer > Properties, and you'll see your system rating there.