Thank you RFM sports!
OK, sorry for messing things up...I may not have a big experience with digital but I do have an experience with photography, so my overall understanding is the following:
AF one shot is the basic stuff, the camera autofocuses and "blocks" the AF
Af servo is suitable for moving objects, and the AF "follows" the movement of the subject
In the AF focus mode, if the subject is still and then starts moving, the camera "jumps" to AF servo in order to keep the subject in focus.
And I know of course that IS in in the lens and AF in the camera.
BUT, I insist that the AF focus does not work correctly when I have the IS on...is this normal, or you rekon that I have a problem with my camera/lens?
I guess that I do not, because with the IS off my AI focus works perfectly! All I want is to understand why this is happening, I am actually in the process of understanding the digital world so everything seems imporant to me.
If you're bored with this thread, I understand...