Mouse "Auto Click" ??

A friend has a CPQ laptop w/XP. It has a strange feature running on it.
When you merely drag the cursor TO/OVER a 'close' or 'minimize' icon on a
window, it ACTS as if you have clicked on the item..
And closes the window WITHOUT actually clicking on it.

I've searched all thru Windows help etc and online but can't find the info
as I don't know what to call it.
It doesn't seem to be referred to in ControlPanel/mouse anywhere.

Anyone know how to REMOVE this feature and get back to actually having to
"CLICK" (or double click) to get the desired result ?

R