If your brother's computer doesn't meed these minimum requirements he may not be able to play Wizard101
What You'll Need to Play Wizard101 Internet: Internet Connection Required Operating System: Windows 98SE or later versions Processor: 1GHz Intel Processor RAM Space: 512 Megabytes Video Card: Best results with GeForce 2 or equivalent (standard in most PCs) Disk Space: 5 Gigabytes
Game Download: The game automatically initiates a download in the background when you log in to play for the first time. The process is transparent to the player. No special installation process is required. You must, however, be connected to the internet.
If he does meet these requirements and still cannot play the game, please contact technical support by clicking on the Help banner on the left here, scrolling down and clicking Mr Lincoln and Customer Support. You will see an Ask a Question tab that will let you submit your question and information.