Selling for parts may yield the greatest return overall but you'll have to go to the trouble of breaking it and listing all the individual components. If you have the time, tools and space to do that you would probably still need to sell pretty much everything to be ahead financially.
My advice would be to give it the best clean it's ever had. Make sure that everything works properly and things like cables, controls and C&S are properly adjusted and lubed and that the bike rides well. Then advertise it and sell privately. Use an advertising meduim that allows you to include pictures and give a lot of information in the ad - particularly in reference to any history that you have on the biike. Some people will be put off by that mileage but if it looks respectable and the documentation backs up that it has been well looked after then it will sell.