I remember reading this kids book around 2008-2012 (probably on the earlier side). The book couldn't have been too old at the time as it made reference to laptops, CD games and joysticks so likely from the 2000's.
There was a boy and girl who lived on a military base. One of them, the boy I think, found a laptop which was made by aliens in space. Somehow the aliens were trying to active something through the laptop and the boy and girl had to fend them off by playing games on it.
The first one was a flight sim type game and the boy plugged a joystick in to fight off the virus.
The second was a chess game. The girl put in a CD chess game and played against the virus on a 3-D chess board.
I think there was a third round but I don't remember what it was or who played it. There could have been another person there. The laptop had the ability to morph to fit both the controller port and the cd.
The cover of the book was space full of stars. There were two speech bubbles coming from different parts of space. I don't remember what the first one said, but the second said "No Thanks" or "We're Good", something like that.
I think it was the setup for a series but I don't remember if there was more. Even though I was young at the time, I remember the plot not being very well written so it might not have gotten any follow-up books.