i used to have a dell xps but im not sure if want to get another dell. what do you all think about this setup and do you think its enough for FSX and good FPS? im new at building my own comp and any replys will be appreciated.
No. You don't need 16GB for gaming, and that RAM is ridiculously overpriced right now.
Get rid of the sound card - they're useless anymore when the built in audio on your motherboard works perfectly fine.
Drop the i7-2600K to an i5-2500K, invest the difference in getting a better motherboard - you want at least a Z68 - H61 is pretty bare bones in the SB line. But you really don't want to use a high end processor with a low end motherboard - that could have the potential to be bad news.
But if you're going to rebuild everything else - you might as well get a case and PSU on top of that - you don't want to try and squeeze new hardware in a case that isn't built for it. In my experience most Dell systems have been proprietary for their parts only - not a lot of standard equipment will fit in these machines.
As far as Wifi goes - I've only really used USB cards - save your PCI-e slots for other purposes.