Best Modem and Platform for TAPI

HI,
 
I'm a student of Computer Science, working on an IVR application. In which I have to make application that will provide functionality of auto answer and student will be able to register courses by following simple steps.
 
I tried lot of sample code on my modem,
"Conexant hda d330 mdc v.92". It provides facility of call dialing and if other person receives the call I can hear him, but he can't (no microphone uses) either.
Is it a voice modem?
 
I need TAPI compliance modem with Caller ID and DTMF key detection facility.
After so much search, I'm still null about this.
Can you plz guide me which modem will be best for this purpose.?
Also guide me which platform TAPI support best? WINDOWS XP or WINDOWS 7?
 
Thnx in advance.
 
Regards,
Hassan Shahbaz.