Can I do this

Could I cash out all my chips, uninstall my poker room software, sign up under a new name and get a bonus for a first time deposit using the same software, reinstalled?

This answer depends on which poker room you are playing through. Some, you can actually cash out your money, and without having to uninstall the software, just create another account and receive the initial first time deposit bonus of $600. Of course, you have to use a different email address than you used to sign up for your first account.