I'm reading the voltage measured on an Agilent 34401 using Single Point measurment in a For Loop (so that I can graph results in real time). The only issue I'm having is that when I try to write the data to a file, it isn't written in two columns (time/loop literation and voltage) like I thought it would be. Instead, it is written as a set of information about each iteration of the loop (including date, time and a bunch of "Delta_X" values). Would anyone know how to write data to a file so that it simply displays in two column form? Thanks.

Use the simple "Write to Spreadsheet" VIs. (They have a slightly different name in 2015). I have it set up for comma separated (.csv) but you can change the delimeter to whatever you want. This is a snippet so you can drag it onto the block diagram and play with the code.