Old themes do not work

I have not found a way to enable the Windows 95 like look to Windows 7's windows. I copied an old look theme from Windows Vista and double-clicked the theme file in Windows 7. It changed some colors but the windows still use the glass-like Aero.

I know that the old look is still there buried somewhere, because after some failed update and restart my Windows 7 desktop looked like in these screenshoots.

Restarting the Windows 7 Beta 1 once again restored the Aero look.

Please, bring back the option to use the old themes (without Aero).
UPDATE: There is an Ease of Access Theme called Windows Classic, which brings back the old Windows 95 style windows.