One thing I noticed is each of your charts are sligtly different sizes so that the number of points displayed on each is a little different. If you want them the same, create one chart, select it, and then do a CTRL drag to make a copy. If you dragged each chart from the palette and then independently sized them, that would acoount for some of your problems. As far as having the x scale with a range of 0 to 100, you can do that by turning autoscale off and then click on the max number on the scale. Type in 100. Since you are using charts, though, as soon as you have reached 100 samples, the chart will scroll. You will reach this fairly quickly as there isn't much delay in the while loop. Then, when you reach the limit of the chart history buffer, you will start to lose data. How long do you intend to let the program run? Also, if you want the charts to start a 0 everytime you restart the program, you have to initialize them back to 0 first. The initialization of charts is covered in the LabVIEW User manual and there is a shipping example called How to Clear Charts & Graphs. Lastly, check the resources available at
http://www.ni.com/devzone/lvzone/fundamentals.htm for learning the basics of LabVIEW. It will be time well spent.