Spec advice needed for new HP PC/Windows 7

is there any diff in getting a CORE i7 as opposed to i5? is it worth it?

Someone else can give info on the processors. I haven't had opportunity to use them. But I've owned a string of HP "off the shelf" desktops. I would look at the peripherals as well as processor set up. I notice many of the newer HP desktops are coming out with plenty of processing power and HD space. But if you look closely you can see often they stick you with slow wired network(10/100 Mbit) no BDROM and they still come with USB 2.0.

I noticed a model on Best Buy that has gigabit network, BDROM as well as DVD burner, 1.5 TB HD and 2 free PCI Express slots. You could use one of the slots for a USB 3.0 card. The price tag was in the $1300 neighborhood and I believe it was I7 processor. Often with these package deals where you get tower/keyboard/mouse a couple hundred bucks more gets a big boost in wired network speed BDROM etc..

Oh, I almost forgot.. this model comes with 10 GB ram and W7 64 bit. When you double click somethin' it should snap open!!

I would get an i7. I have one system with it - it is magic.

Here's an article for you to ponder over..............
Core i5 vs. Core i7: Differences Between Intel's i5 and i7 Processors

I think that core i7, is well worth it, but individual finances must come into play with the cost differential. Only you can make that final decision.