The Cambridge Editions of the Works of Jane Austen (2005) Richard Cronin, Dorothy McMillan

2 drawing-room floor: that is the first floor, as in Northanger Abbey (vol. 1, ch. 4): 'Catherine then ran directly up stairs, and watched Miss Thorpe's progress down the street from the drawing-room window'.
The first floor is the preferred floor for lodgings, and hence in advertisements for lodgings that appear in The Times the phrase 'first floor' is frequently capitalized.

3 every thing to them: that is, they had only one public room that served as dining room, living room, etc.

4 beaufet: sideboard. This is the commonest eighteenth-century spelling for 'buffet' - its etymology is not clear.(p. 562)

2 the baked apples came home: Miss Bates does not have her own oven, and so sends food to the baker's to be baked, a common arrangement at the time (p. 571)

The bakers bake Miss Bates's apples for her — it costs them nothing for the apples to cook in the residual heat left in the oven when the bread is done.(p. lxxii)

Miss Bates tells Emma:
Indeed they are very delightful apples, and Mrs. Wallis does them full justice -- only we do not have them baked more than twice, and Mr. Woodhouse made us promise to have them done three times -- but Miss Woodhouse will be so good as not to mention it.(Ch. 27)