Does MED3201 support Windows NT?

Since this product has been phase out, it hasn't released the driver of Windows/NT still.

Does MED3201 compatible with Direct X5?

No, the MED3201 only support Direct X2.

Scratchy sound particularly when WIN95 is loading and McAfee?

If you get the noise from the sound card, please check the IRQ and I/O values in the system properties.

Is there any driver that can support M-Soft SideWinder-pro on MED3201?

There is only one driver for this card. Since the M-soft sidewinder is newer joystick the MED3201 is too old to recognize it.