Heres one thats bothered me for weeks, and seeing as i'm here, i'll try the pleading for help for the second time today.
On loading many games that open their own screen, near enough to instantly the screen reverts back to windows, minimising the game screen to the task bar. I have to go through clicking the taskbar button (the one just minimised there), watch the game screen reload, then watch it switch back to windows and minimise again. It takes upto several loops of this clicking and loading before the game screen finally stays on show.
I have absolutely no idea what caused the problem. It doesn't matter what the age of the game is. modern titles such as juiced, nfmw, nfsu2, sim city 4, football manager 2006 all do the same thing as old titles such as the command & conquer titles.
It's normally caused by software running in the background. try exiting any non essential software running (right clicking taskbar items etc) and playing the game then. If it works, you can restart them and test one at a time, to see which is the culprit.