Well in my opinion the first one is lacking a reference to a point in time. The second one I would use when saying something like "She's cooked dinner so we can eat now." The first one I would use to express something like "She cooked dinner yesterday, today it's my turn."
OK, fine, I just wanted to know where you were at.
Generally, the addition of these adverbs seems to emphasize the connection to the present. So, in general, I prefer the Present Perfect with them and not the Simple Past. But I think you need to look at the individual sentence, and also the context, which we don't have here.
That sheds some light on the whole issue. Coming from a German background, present perfect is one if the hardest things for me in English. We use it all the time, which makes it hard for me to use in English, because I know it's different there.
I couldn't think of a context for the simple past version off the top of my head, but I believe I understand the concept.
As a final comment, don't get the mistaken idea that we English speakers always think carefully about the nuances before choosing a tense or making a sentence. We don't.
One of the signs that someone who speaks Engish well is not a native speaker is often that their English is too careful and precise.