I've been using QuickBasic for a few years, and whenever I wanted to shell to another program, I used

shell "programname" .

I've looked for an equal set of instructions in Assembly Language, but I have had no luck so far.

ShellExecute

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/shellcc/platform/shell/reference/functions/shellexecute.asp

derived from shell32.dll

HINSTANCE ShellExecute( HWND hwnd,
LPCTSTR lpOperation,
LPCTSTR lpFile,
LPCTSTR lpParameters,
LPCTSTR lpDirectory,
INT nShowCmd
);

Is there a DOS function that will do the same? Part of int 21h maybe?

Many thanks!