How can I copy or reveal email password dots to text on my iPhone 4 running iOS 5.1? I have tried going to Settings -> Mail Accounts -> Gmail -> Account, but it only shows my password in dots and also does not allow me to copy it.
You cannot. If you could copy it, someone who had your iPhone could find out your email password by copying it.
If you lost your Gmail password, you need to contact Google so they can reset it.