My XP Pro sp3. Has been loading /running normally for a very long time.
What is happening now is that on boot up it goes normally through POST > windows splash screen> loading desktop and taskbar with all icons.
Then one of two things will happen.
1/ The mouse curser can be moved around the desktop but remains in 'busy/working' icon and you cannot load anything and ctl+alt+del will not work.
2/ Everything looks normal on the desktop including the mouse curser which you can move around but clicking on any shortcut does nothing and if you take the mouse curser to the taskbar at the bottom it shows busy/working icon again.
The only way to exit is by pushing the reset button.
I do dual boot with Windows 7 & XP and the dual boot option works normally and I've been dual booting for over a month now and was not having issues with XP. The same mouse/keyboard is connected for Win7 as for XP and works fine in 7.. It's the same mouse/keyboard I've had for a long time with this XP.
Dual boot is with both O/S on a single HDD.
I've not added any new programs to XP other then normal updates.
For virus protection I have ESET Node32/Malwarebytes and Spybot. All have been on XP for some time.
Smart testing shows HDD to be good. I've not run memtest but then I'm using the same hardware in 7 without issue so I don't believe it's a hardware problem.
All operating temps are good.
If I do get XP to load properly and it sometimes will but not often then no test I do show ups any errors.