Cant get pass the "press A button" screen

I suggests you to call nintendo let them diagnose the unit. Maybe they have some software or firmware update for wii. Re-flashing or updating the firmware may fix it.

Try this:

1 Turn the Wii console power OFF by pressing the POWER Button on the front of the console. Unplug the power cord from the wall outlet for a few seconds. After a few seconds have elapsed, plug the power back.
2 Turn the power of the Wii console ON. When you see the Health and Safety screen, open the small flap on the front of the Wii console to find a red button labeled "SYNC." Press and hold the SYNC Button down for 15 seconds.
3 After holding the SYNC Button on the Wii console down for at least 15 seconds, you can now "re-sync" your Wii Remotes:
a With the first Wii Remote you wish to sync, remove the battery cover on the back of the Wii Remote to find a small red button just below the batteries.
b Press and release the small red button just below the batteries on the Wii Remote, the blue lights on the front of the Wii Remote will blink.
c Quickly press and release the red SYNC button on the inside of the white flap on the front of the Wii console.
d When the Player LED blinking stops and stays lit, the syncing is complete. The LED that is illuminated indicates the player number (1 through 4).
4 Start the game from the Wii Menu, then sync the Wii Balance Board from the opening screen of the game.

If still didn't work better have the Wii replace from walmart since its new..

Hope that helps.........

Unplug the WII from power for ten minutes this should reset it and clear the message.
Try also Pointing remote to Wii Sports in upper left corner and press A

Turn off for a moment, try again, reconnect your controller.

Since its brand new, you can get it replaced if that doesn't work, dont waste your energy on it, just get another one, free replacement / warraty. Im sure.