Taskbar mouse pointer disappearance issue

This is not really a huge problem but it bugs me as i use the "peek at desktop" function in explorer all the time..

THe problem is that whenever i put my mouse pointer around the bottomright corner of the screen, it disappears only at specific places...

It's hard to explain but here's a video

Apparently, screen capturing software doesn't capture the disappearance/reappearance... so i filmed it with a digital camera..

I isolated the problem and found out that it was something within the external monitor (i use one) or the external monitor's cables that was causing this probelm.

when i disconnected the external monitor, the taskbar on the laptop screen didn't have this issue.

does anyone know what is wrong?

sorry for the confusion, but when i meant "it disappears only at specific places" i meant the mouse cursor..

Please watch the video if it is still confusing.

Like i said, i use it all the time, but the mouse cursor disappears sometime, so i was wondering what the problem was.

Hmm.. the issue still persists.

and i found out one more thing: when i put the mouse cursor on my laptop screen bottom right corner (the external monitor is still connected at this point) where there is no taskbar, the the problem is still there...

how can i reboot in safe mode? my hp laptop doesn't give me those options on startup or when i go into the options it does give me

i've tried F8.. no good.
maybe F11?

exact same problem in the same place but i have two monitors and it does the same thing on both of them. whether the taskbar is there or not. so just the bottom right corner of the screen.
I've turned off aero, updated graphics drivers, changed resolutions and still had the problem.
had the same graphics card in my last win 7 system and didn't have any such problem.