Hello,From your pictures I determined you have plaster walls. Plaster is different from sheetrock as it is much harder. The cracks are common to old plaster and are fixed by first taping them with fiber mesh tape,then coated with either durabond setting compound or sheetrock compound like say a plus3 brand or proform lite blue. Durabond comes in powder form and is mixed with water to a peanut butter consistency or til is somewhat easy to apply.After two coats sand smooth with 120 grit sandpaper or a sanding sponge. As for the hole first fill with compound then tape over it then coat it again. Oh before I forget durabond comes in different setting times. I suggest 90 minute or 210 minute.