I don't fully understand...when in input box, or passing over text, isn't it normal to see the avarage text cursor?!
The vertical line isn't.
Go to control panel and choose a different pointer scheme (for all cursors) see if same behaviour...
Check colour depth of the cursor compared to the colour depth in your Display properties. A higher colour depth cursor and a lower Display can cause glitches.
For the vertical line you're seeing, try lowering your hardware acceleration slider one step .
Have U installed anything to personalize your pc lately?! or do U use themes?