Could the OP be also looking for advice re the number or "well known" songs V own material?    i.e. how to balance out the hour?

If so, then unless you already have a reputation as a good song writer/composer it's always best to balance your own material with that of others and/or traditional material. I'd say about 50:50 but it will depend on your experience and reputaion.

Sorry, if that's not what you meant. ;-)

Other than that, if we're just talking about a total number of well known songs it will depend on their length. It's probably best to not to have too many really long ones and a balance is important.
I'd say that ten to twelve would probably be about right and to keep the chat brief unless you are really good at that or it is a popular part of your act.