Well, look at the ability text:
PRD:
Deliver Touch Spells (Su): If the master is 3rd level or higher, a familiar can deliver touch spells for him. If the master and the familiar are in contact at the time the master casts a touch spell, he can designate his familiar as the "toucher." The familiar can then deliver the touch spell just as the master would. As usual, if the master casts another spell before the touch is delivered, the touch spell dissipates.
can the wizards attempt to deliver it himself?
By a strict reading of the familiar ability text, no. When the spell is cast, the wizard designates teh familiar as the "toucher". From then on, the familiar is the one that must "touch" someone to get the spell to go off. There's no provision for moving it back to the master.
does the familiars attack count as the wizards standard action?
No. The actions of the familiar and the wizard are entirely separate. If the familiar hits or misses, the wizard can still cast a spell that round (though the familiar can't hold a charge after the wizard does so). This is much the same as how the master can move, cast the touch spell, the familiar can then move, and make an attack all in the same round.