Very, very, very odd mouse problem..

[Celeras]

Here's the jist. Sometimes after playing World of Warcraft for a few mins, the cursor will freeze on my mouse. Not just in game but on the desktop as well. JUST the cursor freezes, the mouse still works fine. You can still right-click/click whatever you want, even though you cant see where you're clicking. If you're good, you can 'ghost' the mouse to the start tab, and restart the computer the old fashioned way, in which case the problem goes away. It cant be any power/driver issue, because the mouse still works.. it just the cursor that freezes. Anyone have any idea? Its only happened a few times, but its rather annoying.

Also, by 'ghosting' the mouse ingame, i can somewhat remedy the problem. In the video options, there is an option for 'hardware cursor'. If I ghost my mouse to that after it froze, and uncheck this option, the mouse now works... in the game only. If I alt-tab to the desktop, that mouse is still frozen and I have to ghost. In addition, when I uncheck this in the game, the 'normal' white mouse arrow will appear on the game screen, frozen, while im moving the game mouse around.

**[edit] It also seems that I can remedy the problem by reseting the resolution. Perhaps the 'hardware mouse' option in the game has nothing to do with it at all, then.

Specs, all brand new, PC less than a week old:
======================================
CPU = Intel 3.2ghz, Prescott
OS = Microsoft Windows XP Service Pack 2 Ver 5.01.2600
Version of DirectX = DirectX 9.0c
Main Memory = Capacity: 1022MB : Free Space: 728MB
Graphics Card = NVIDIA GeForce 6800 GT
Type of Chip = Unknown Video Chip
Video Driver = nv4_disp.dll
Version = 6.14.10.6702
Updated = 11/15/2004 03:17 PM
VRAM = 256.0MB
AvailableVidMem = 245.0MB
AvailableTextureMem = 299.0MB
Sound Card = SoundMAX Digital Audio
Sound Driver = smwdm.sys
Version = 5.12.01.3630
Updated = 06/02/2003 01:42 PM
Network Card = Intel(R) PRO/1000 CT Network Connection
Network Driver = e1000325.sys
Version = 7.0.37.0
Updated = 05/20/2003 02:36 PM
Motherboard = P4C800-E
Manufacturer = ASUSTeK Computer Inc.
Version = Rev 1.xx
======================================

Any ideas? Could it perhaps be some kind of IRQ conflict? My IRQ16 is being shared by the Video card, and two Universal USB host controllers. Yes I'm using a USB mouse, this is the way the computer allocated the IRQs default. I was told that just because theres more than one thing on the IRQ, that doesnt necessarily mean theres a conflict?
Any suggestions would be helpful, this has me stumped.