Sufficient yes, but the brand is maybe a touch iffy. Lenovo has done a real bang up job of driving IBM's top rate computer business absolutely into the ground quality wise.
Personally, and you're free to heed or ignore this advice as you see fit, I'd be focusing solely on Dell, Apple, and possibly Asus though I'm a little hesitant on Asus mainly since they haven't been making full on computers for a long time. Early signs are encouraging, but they've only been at it for a couple of years, so hard to get any kind of long term trend info on quality. Anything else I would probably not buy.
But specifications wise, that system should be more than sufficient for quite some time to come. It might be worth splurging for the i5 however, just so you have four physical CPU cores instead of two hyperthreaded cores. A little bit more money now will likely mean she can get an extra 12-18 months of usable life out of the unit, maybe more.
I am looking for a PC for my
sister-in-law. She will not be doing any tedious tasks regularly, but
on occasion wants to do some light photoshop and video editing of her
family videos. She will be mostly cutting out unwanted scenes either
mini DVI captured tape or her newer HD flip using flash media. She
will probably use Adobe Premiere Elements and Photoshop Elements. She
is a single mom and I am trying to keep the costs down as much as
possible. I was looking at PC's with an Intel i3 such as this
http://www.staples.com/office/supplies/StaplesProductDisplay?&storeId=10001&langId=-1&catalogId=10051&partNumber=389456&cm_mmc=Shopzilla-_-Shopping-_-Technology%253EDesktop_Computers-_-389456-77523HU&cid=CSE:Shopzilla:Technology:Desktop_Computers:389456:77523HU
is this sufficient or does she need an
i5?

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