Android 2.2 Froyo… My head is full of Android 2.2 Froyo now. Forget about Windows Phone 7 support on HTC HD2. In order to have Android 2.2 Froyo HTC Desire ROM on HTC HD2, we need to flash HardSPL3 on HTC HD2. Then flash newer HTC HD2 Radio ROM with CustomRUU. And install any Android ROM that suite you.
Download HTC HD2 Radio ROM here