If you create a column with your dates (or row), 9/1, 9/2, 9/3 ect, select all your data points and then right click > go 'Format Cells' > select the 'Number' tab > Select category 'General', that I would assume should fix the issue of your input reverting back to 9/1/2016 ect...

RE your second question, have you tried turning off the 'Data Labels'? Click on the graph, and if you have excel ED 2013, click the green arrow that appears at the top right of the graph, deselect 'Data Labels'