I am using Ubuntu 13.04 Desktop and I'm happy with it. However sometime I think the older versions were better as they were lighter or utilized less resources.
Is there any way that, it will ask me during every boot time to choose a different settings or GUI (maybe) so that it will utilize less resources. I don't want to uninstall/loose anything permanently.
Note: Again I am happy with my current full featured Ubuntu Desktop.
I have read about Lubuntu, can I put it beside/within my current Ubuntu installation without loosing anything? It will appreciate if there is any other better idea.