I have used a similar JVC HDD camcorder and no drivers were required, at least on Windows XP. To the PC, the camcorder is seen as an external hard disk and a flash memory card reader for its SD slot, which appear as two separate drive letters.
The CD that came with the JVC camcorder I've used only contains PowerProducer for making a DVD from the footage. However, the disc does not contain any drivers from what I recall.
If you're using Windows 2000 (with service pack 4) or Windows XP:
If Windows insists on a mass storage driver, there is a good chance that the INF file Windows uses when installing new mass storage devices has gone corrupt or the folder containing INF folder has been removed.
To check the INF file, go into OS drive (usually drive 'C'), then into 'Windows' and into 'INF'. Check to make there is a file called "usbstor". In Windows XP, this file size should be 14,578 bytes. If this file is missing or worse still, there is no 'INF' folder in your Wndows folder, you should carry out a chkdsk on your OS drive as this is usually the sign of file system corruption. If just the 'usbstor' file is missing, you can try copying it from another PC running Windows XP or the same OS you're using.