How to open Word douments in single instance using vc++

Dear Experts ,

I am developing application that Launch word application using VC++ .
using Office 2002

After Launching word i am opening doc file [ C:\tmp.doc] . i want to
know how i open
multiple doc files in single window of word .

i have tried the option in word : Tools > Options > ViewTab > Windows
in Taskbar [unchecked] .

if i unchecked the option then all my documents open in single window

but can u please tell me how to achieve this progamitically . For more
information
i am not using word automation in my application. i am using simple
ShellExecuteEx API for this purpose .

if Any registry setting for " Tools > Options > ViewTab > Windows in
Taskbar [unchecked] .
" let me know. this will be easier for me to code rather than
going for automation in word.

Thanks In Advance

Regards ,

Jignesh Patel
Surat