Greetings,
I'm pretty sure the game you are talking about is tank I. I have played it as part of a gaming console called Family Video Game, which was a NES clone.
http://www.geocities.com/s_h_3/ninte...ily/family.htm
Unfortunately I haven't been able to find any screenshots from the game.
EDIT:
Found it.
Apparently it is also called battle city.
http://www.mobygames.com/game/battle-city