If I were you I would look at having a good receiver first! HTIB arent to bad to start out with ( as I am assumeing this would be your first HT system?)... but as you "grow" into it you will always get the bug to upgrade.
I started out with the Onkyo HT-sr800 HTIB they had on sale 4 yrs ago as it was a decent set up, it worked great for my first HT system. As I got the bug to upgrade ( it all started because I had to much clutter of wires/cabels beind the cabinet and wanted to clean it up by having a receiver with more HDMI hook-ups) I searched for another receiver that had what I wanted so I stayed with the Onkyo brand and got the mid level Onkyo 808 series. When I repleced my older receiver ( still using the old Onkyo speakers at that time) it was like a night and day differance! It made the old Onkyo speakers more "alive" to say the least.
So in essance, look at getting a good receiver at first. Make sure it has all the feautes that you want such as 5.1,7.1 or 7.2, power, size, HDMI I/O and so on. If you check the internet such as Amazon.com, Vanns.com, Newegg.com and so on you can find some realy good deals from time to time.
Speaker wise, the Def. Techs are a really good speaker but as mentioned the 800 and 1000 series are going to be your best bet if you are looking into those. Oh course with a decent receiver and adding either the 800 or 1000 series + a decent sub that will put you well over $1k, closer to $1,500 depending on what you choose that is.
As a good start the Dennon 1911 or even the 1611 will work just fine. THe Yamaha V677 or even the Pioneer 1020 will work good too! Onkyo RC260 or 608 is an excellent one too... it all boils down to what you want that is.