Not an easy question to answer, it depends what you are looking for. But if you want to know where some of the nicest and most expensive houses are located I would suggest the following roads:
Garlies Road, Allenby Road, Horniman Drive, Liphook Crescent, Wood Vale, Honor Oak Road, Dunoon Road, Thorpewood Avenue, Rockbourne Road, Gaynesford Road, Vancover Road, Lowther Hill, Brockley Rise (North), Honor Oak Rise, Canonbie Road, Netherby Road, Radlet Avenue, Hengrave Road, Redberry Grove (some are not in SE23 but are on the borders).

Of course there are some great houses on other roads and some of these roads rarely have houses on the market (especially at the moment). And virtually every road in SE23 is a 'nice road'