Yeah, I would just breath about how you are going to go about it. Like in the middle of the night raid on the stuff, etc. Have a speech prepared, have a day out thought of and maybe even a choice for it to be one place or another better yet, both. Have more outings for a while to get their minds off of it.
I have always looked at this issue with complete dread. I look at those game systems and hear the older kids talk and I get weirded out. It seems so consuming. I really want to give my kid some options, but I will never, ever, ever let them have hours unless for one day a month, called on and for and nothing else, not even sick. I will be so uptight... TV, the whole deal.. you mamas I know are real people and I do spend a good 3 hours here sometimes twice a month but really can't get more and it does go in spurts. I don't need tv.. I feel a deep magic in myself when my hobbies/dreams, and goals/dreams, and even deep love with DH/dreams come to be and the whole plugging into things is not a way to live those.
I had cancer and gave my son TV (oh I was pregnant with it/surgery.. and then colic baby) I eventually got him into a Montessori Pre-school and that helped. I am very strict about the screen time now days. I have no structure, but we might have a lot more self-kid work around here and it takes a long time for them to help out. I put all kinds of school-ish properties on being neat and clean, right down to sweeping being cross body brain what evers. We make fun food mostly healthy food, we all help out in almost every area and then yes, he can watch a couple edu type shows if he wants to on a rainy day or while sister naps, but the less it is on, the less it is in his soul to want.. He is a very bright boy and I totally got to him about his dreams not being to watch tv all his life one time and tried to explain lightly that we moved and it was a lot of work, the TV helped us get through all the changes but it is over now. I am so honest with him but not really, it is a light level of emotions because I know he needs me to be that ground and I am much more explain how life works.
(he is 4 now, siggy won't change) "Fred, you are going to be knight, a shining knight, that flies planes, rides motorcycles, climbs trees, swims raging rivers and finds the sweetest rose to give to your wife some day. TV day after day after day weakens all those dreams and that power. Playing, eating right, laughing, talking to your neighbors or forest friends (etc, etc, etc, etc.. and I go on) is going to open doors to your whole life. You are going to get better and better until you are.. ahh, all grown up and a **stunning** man... and you will hold your dreams right here (point to his heart) and that is going to take you sooo far. TV can't give this to you because all you do is sit down. A little bit is okay, but you gotta get out there and be *****Freddddddyyyyyyy!!!****"
That was my big talk when I got busy for awhile and my love, SAHD, went over board with screen time recently. It worked sooooo well.