String buzz can be because you tuned the guitar an octave to low and for beginners it may sound in tune but it isn't and therefore the strings are to loose and you get buzz, the scale finder is not the tool to tune a guitar.
To put the strings on you pul them through the tuningpeg's hole and you put your hand loosely under the string on the fretboard ( doesn' t matter where on the fretboard ) and then you follow chris is instructions on twisting and turning, if there is a stringtree, don't forget to put the string under that to.
Second; if you try to form a chord do you keep your thumb behind the neck? if not you should.
Third, don't start with the C chord, Liza says in GF1 " the simpel C and G chord", well there is nothing simple about those 2 chords, actually, lots of people taking private lessons quit because they can not form these chords and teachers are to stubbern to see that, start with a simple form of the A chord; middle finger 2nd fret 4th string, index 2nd fret 3rd string and ring on the 2nd fret 2nd string, from this shape it makes it easy to learn the D chord and E chord without moving to much.
Fourth; don't sit in a chair for learning but stand up right with a guitar strap, better posture and better holding on to the guitar.
If it still doesn't work to grasp chords then there are always other guitars with smaller necks.
And the last; I think personally that every one can learn to play guitar, at least at a level that they can strum along with easy songs, the only difference is that some people don't have a feeling for rhythm or music at all but that are only very few.