We have found that we tend to run the entertainment gear on 12v, rather than turning on the inverter. Mainly because of the perception of power wasted due to the inverter. `We currently just use a laptop for DVD's. This is also our backup comms/navigation computer. Have thought about getting a car DVD unit for above the bed, but have resisted that urge so far.
What are you going to use for audio/news? We use WorldSpace radio connected to our stereo, good sound quality and fair amount of variety. Added bonus is the weather data, great charts and sat photos.
Are you still hoping to get away this year, if so you may want to put off buying electronics until you get to Singapore.