Is it recommended to get more Bitcoins on addresses which contain already Bitcoins?
No, you should never reuse addresses. With a chain analysis you may get yourself traced. Better just use another one each time, it's for your privacy.
If it is better to select empty addresses: Should I use empty green "receiving" or empty yellow "change" addresses for it?
The word says itself; receiving addresses, when you want to receive bitcoins. Any change you have when you spend from your receiving addresses goes to the change addresses. You can obviously spend from those too, it's just a way distinguish your money.