Vista - Mouse failure on startup

OS: Vista Home Premium (32bit) SP2.
Mouse: Your normal USB HID-compliant mouse.
Driver: Unknown from Microsoft. Version 6.0.6001.18000.
Number of USB 2.0 Ports: 4 (Motherboard) + 4 (seperate circuit board)

Problem details: After installing SP1, I encounter a mouse failure on startup; cursor present, mouse detected and driver already installed, but unable to move the cursor or do a click. No problems without SP1.

Pulling out and plugging back the USB mouse into (1) the same port and (2) into a different unused port fails to resolve. (3) Swapping the mouse and keyboard USB ports fails to resolve.

(4) Uninstalling the mouse driver through Device Manager, then performing actions 1 to 3 fails to resolve; no bubble pops up saying "installing plugnplay device".

(5) Uninstalling the USB HID driver instead (Version 6.1.6002.18005), then performing action 1 to 3 temporarily resolves the problem; PlugPlay will install the driver (bubble pops up); mouse working after installation is complete.

After a reboot, mouse failure repeats itself. For the last 2 days of 10+ reboots, only 2 consecutive restarts did not have a mouse failure. Just a while ago I rebooted twice to a mouse failure.

I have disabled some services from starting. From what I know, I have not disabled any which are required by the mouse. I have attached a list of services on my computer.

is the driver for the mouse the most current up to date version?