This can be a bit daunting if you have been out of the audio world for a while. I would start with your room first and make sure it is well designed. You can avoid a lot of problems by spending some time and money there.
As others have said you have an opportunity to put a "system" together instead of piecing components into a whole.
Trust your ears. Specifications are rather meaningless.
Consider the support of the dealer and the company that manufactures the gear. If you have a problem can you really get something fixed?
If you are careful, you can put a really nice system together so visit as many dealers and shows as possible.