Halacha: "Candle Lighting on Shabbat"

B"H

A Sephardi Rabbi on Israel's haredi radio channel "Kol HaRama" explained the following:

First, the Rabbis asked the question whether a Jewish woman has to say a blessing over the Shabbat candles which were lit by a Gentile. In some cases it can happen that a Jewish woman is unable (e.g. an illness, etc.) to light her Shabbat candles and, instead, asks a Gentile to do this for her.

The answer is that a Jewish woman should only say her blessing over the Shabbat candles when she actively lit them herself. Halacha demands a person to do something. Do it with one's own hands. When the candles were lit by someone else the woman cannot say a Bracha (blessing).

Second question:

Is a Jewish woman instantly accepting Shabbat when she lights her candles ? 

Meaning, is she after candle lighting forbidden to do any further work in order not to break Shabbat ?

Answer: 

The Shulchan Aruch says that if a woman lights her Shabbat candles with the intention of not yet accepting Shabbat, she is allowed to do further work even after candle lighting !

We light Shabbat candles in order to cause a special Shabbat atmosphere and fill the house with light. However, lighting the candles has not entirely to do with accepting the Shabbat.