I had a very similar problem a couple of days ago.
Reinstalled XP about a month ago and couldn't get USB2.0 to work at high speed for uploading camera photos / downloading music to my phone. Found this:

www.tomshardware.co.uk/forum/page-37818_35_0.html

Or, more specifically, the following info:

To install USB 2.0 controller drivers

Before completing this procedure, determine if the USB 2.0 controller
drivers you have on your computer are installed. To determine this, do the
following:

1.. Open Computer Management.
2.. In the console tree, click Device Manager.

a.. Computer Management
b.. System Tools
c.. Device Manager
3.. On the View menu, click Devices by type.
4.. In the details pane, click the plus sign to the left of Universal
Serial Bus controllers.
If the word "Enhanced" is included in any of the listed controllers, your
computer has USB 2.0 controller drivers installed.

If you cannot find the word "Enhanced" in any of the listed controllers,
perform the following procedure:

1.. Stop using any USB devices (such as a printer or Web cam) except the
mouse and keyboard.
2.. In the details pane, click the plus sign to the left of Other devices.
Then, under Other devices right-click Universal Serial Bus (USB) Controller,
and then click Update Driver.
3.. Follow the steps in the Hardware Update Wizard to complete the
procedure. When you are finished, you might be prompted to restart your
computer.
Notes

a.. To open Computer Management, click Start, and then click Control
Panel. Double-click Administrative Tools, and then double-click Computer
Management.
b.. If Universal Serial Bus (USB) Controller is not listed under Other
devices, you cannot install a USB 2.0 driver. To find out more about
installing these drivers, contact the manufacturer of your computer.


It's a bit beginner-y, but it worked for me where all else failed.
(WillI'mNot logs in twice a year, every year, Wed 30 Sep 2009, 3:31, Reply)