OK, first i want you to try this:
START > PROGRAMS > Aces High II > Aces High II Film Viewer.
If that doesnt work, open Windows Explorer (NOT Internet explorer!) and try to find your game installment folder (default would be C:\Programs\HTC\Aces High II\ - but since you reinstalled windows without it being deleted, i guess its somewhere else). In the folder, look for the ahfilm.exe file. Double click it to launch the film viewer (if that works, just create an alias on your desktop by right clicking it and "send to desktop").
If you dont find the game folder, search your computer for ahfilm.exe.
If you cant find that, im afraid you will have to reinstall the game. There is no separate download for the film viewer.
If you *find* the ahfilm.exe and get an error message *launching* it... see if you can launch the game (DIRECTLY, through the exe file in game install, not through any alias or start menu). If that doesnt work, something got messed up with reinstall of windows.