If you want it to be future proof, don't buy 775, it's a dead socket, it's just as dead as 939, 754, 478 etc.
If you want more power, don't buy an E8xxx series, go amd and buy a 720, it's cheaper and more powerful.
So Q9550 or 9450 if you can find one, or a 720 for $150 cheaper and you could get DDR3. Also in some places the I7 is less than the Q9550 so you might be able to get an I7 build, especially with a $1000 budget.