MS DOS WORKING

Hello,
Presenly I am learning C++ language . when I quit the turbo c programme the scren goes black and PCdont respond .I have to restart my PC . Same things happen some other accounting programme which run in MS Dos . Whenever I quit thse programmes Idont return to windows . Previously a MS Dos logo used to be there on icons of these programmes but now there is no such logo . please help me so that i can easily quit these programmes and go back to windows .
thanks.