Thanks.
Next - how fast is fast enough and how much of a price premium is it worth?
If you are talking about the internet & doing things there, you speed will be limited not by your processor, but by your Ethernet card or wireless devices & the connection speed of your ISP & also by the individual websites you are using.
For office type apps, like Excel, Work or PowerPoint, they should open within a couple of second of starting them.
If you are having to wait for more than a few seconds for an application to run, or do tasks, it's too slow.
An i5 running at 2.6 Hz or better with 6-8 gigs of memory will easily satisfy you................unless you are doing lots of graphics work or playing high end games w/o a separate graphics card.
MM