have you looked at any hps lights if you are going to continue to grow would go ahead and invest in a decent light to flower with.
as per fixing these plants well you cant really fix them at best you could keep the new growth more compact the old growth is going to always look stretched which is why you should probably go ahead and flower them if you are going to, if you start more seeds and keep them close to the flouros instead of leaving them in the window for 3-4 weeks they would look alot better they would be alot more compact with a shorter distance in between internodes. while that light you linked to would probably work ok for a scrog or as one out of a 3-4 lights system if you have no other option and have to use flouros instead of getting a hid you can cover more area with more bulbs even if they were less wattage using 4 25 watt cfl bulbs is going to allow you to position them close to the plant like one at the top and and a few along the sides. its true all lights will lose intensity the further away they are but atleast hids give you a little bit more range to work with.