Press Up, Right, Down, Left at the title screen (where you normally press A and B). The cheat menu will appear. Enter one of the following codes at the "Cheat" menu to unlock the corresponding cheat option.

Everything unlocked
Enter Nothing But Hope as a code.

Turn on Blox time
Enter Freeze Frame as a code.

All Colored Blox
Enter Rainbow Blox as a code.

1 million Boom Bux
Enter Bailout as a code.

All sound effects are Virus Blox sound effects
Enter Musical Fruit as a code.

All animations turn into flowers
Enter Blox Bouquet as a code.