1. You should be able to use the "external USB Acom Data USB 2.0 100 GB hard drive" on your Windows 98SE system. The
www.acomdata.com website indicates that their drives are sold with a CD containing the necessary drivers (and are compatible with both USB 1.1 and 2.0 ports). You may also download the necessary drivers from their site:
http://www.acomdata.com/scripts/downloads.aspThey have a limited selection of 100 GB drives, so I'm guessing you're looking for "Device Driver for External Hard Drives - USB 2.0 (Version 5.16 for Windows 98)"; but only you can determine that.
http://www.acomdata.com/customer_support/hd-support.html2. Windows 98SE does not provide native support for most USB devices (exception is USB keyboard and mice using legacy USB BIOS support). For other USB devices, you'll need to install a suitable driver. These drivers are provided by the manufacturer of the device.
3. General Installation Procedures for Windows 98 SE (check their user manuals if you want procedures from AcomData).
a. Install the USB 2.0 driver for the external hard drive.
b. Reboot the computer (on general principle for Windows SE operating system)
c. Connect "b" connector of USB cable to the external hard drive.
d. Connect power to the external hard drive and turn power on.
e. Connect "a" connector of USB cable to USB port (on computer - preferably a USB 2.0 port on back).
f. Device should be automatically detected and configured.
The reason you install the driver and power on the external hard drive before connecting it to the computer is so the operating system can detect the type of device connected (device tells operating system what it is when asked) and find a suitable driver (because you've already installed the driver).
Your device is probably backward compatible with a USB 1.1 port, but it will be slow. So slow (for a 100 GB device) that you may think the device is hung. Really should be using a USB 2.0 port on the Windows SE computer.