You don't need a lot of advice--you've chosen your equipment very well, with only one obvious exception. Apex is an off-brand with a poor reputation. A name-brand DVD players (Sony, Pioneer, etc.) will serve you much better.
The other thing you shuld do is play around a little with speaker positioning--it can make a bigger difference than changing anything in your system (the Apex excepted).
The other thing you shuld do is play around a little with speaker positioning--it can make a bigger difference than changing anything in your system (the Apex excepted).