NipunNZT240

My car is Allion 240 2002,Its done around 15 outstation and 10 in city, what should i do for more fuel efficiency.. Its done 80000kms

Need some advice friends.. My car is a allion 240 , It is equipt with original audio player.. But not compatible with dvd. So I looking forward to buy one.. What I need to know,Is that all DVD players are in a standard size that fits to different vehicles, Or are those players different to each vehicle.. If so what kind(size) of Player should I purchased for my allion 240. I need this advice Cz im going to purchase that from ebay.. Thank you,,