I second samtregar, Google Charts are really quite nice. Here is a dummy for your data (what part you included): http://chart.apis.google.com/chart?chd=t:98,95,83,75,98,95,83,75,98,95,83,75&chs=200x100&cht=lc&chds=0,116&chxt=y&chtt=My+Lovely+Graph.

GD is easier to get going than ImageMagick (I've never been able to install it on any of my boxes and it caused problems at work too) and does this sort of chart quite nicely. I don't know if it's Windows compatible though. :(