I too am having problems with rooting my 101 G9.
The problem I am having is with the USB driver. The driver provided by Archos does not appear to work on either x86 or x64 systems. If I enable USB debugging and connect the device, everything goes fine up until it finds a device called ARCHOS, which it cannot find the driver for, even if I direct it to the folder containing the unzipped Archos drivers. It simply says that a compatible driver cannot be found. The exact same thing happens if I plug it into my x86 Windows 7 machine, or my x64 Windows 7 machine.
MTP and CTP modes both work fine, despite this! I can open up the device in Windows and browse/copy files as normal. But "adb devices" shows nothing at all.
HTC Wildfire S A510e (S-OFF, unlocked, rooted, custom Android 2.3.8, de-Sensed)
Motorola Defy (red lens, unlocked, rooted, custom Android 2.2, Motoblur)
Archos 101 G9 Turbo ICS (rooted, custom Android 4.1)
Motorola Razr i (unlocked, rooted, custom Android 4.2)
HTC One (S-OFF, unlocked, rooted custom Android 4.4.2, Sense 5.5)