This will amount to environmental pollution and considering that TVs contain parts that are explosive, you should not do that, but you should dispose tem in the right manner. You can take the TVs to recycling plants that accept them or donate them. Visit http://www.epa.gov/osw/conserve/materials/ecycling/donate.htm for better suggestions on where you can donate your TV to.
Ok let me save you time. An old tv Screen will not blow up when shot, trust me. Don't do it, it might seem like a fun idea but it's not really and a big mess to clean up. You'd be better off shooting full water bottles.