Swapping to VM

Hello all,

Recentley ive found myself in the position of managing 100 mac laptops, all of which are to have parallels running on them with a windows image. ive seen a solution on a contracted technitians laptop where he simply pushed a few buttons and the screen slid down reveling the windows OS, then again 2-3 buttons and back to mac. i believe he had a excel spread sheet open in mac at the time.

I was wondering if anyone might be able to help or advise on what paralells might offer or if there is a shortcut that can be setup to replicate this sort of function to make the process easier for users to migrate to the mac environment.

(this is going to be a learning enviroment within mac and a financial administration system within windows)

If at all possible it would be realy handy if the shortcut were to work from any window at any time within mac even if the parallels program is closed at the time. (am i venturing into the world of mac scripting or using automator? neither of which i have any experience with)

Thankyou and i look forward to your replies.