The humorous phrase to make a better door than (a) window means to obstruct a person’s view. This phrase is chiefly used in you make a better door than (a) window, addressed to one who obstructs the speaker’s view.
—Cf. the synonymous phrase is your father a glazier?.

The phrase to make a better door than (a) window occurs, for example, in the following from Stan and Don show sees FAI’s bread boy rise to the occasion, by Billy Keane, published in the Irish Independent (Dublin, County Dublin, Ireland) of Saturday 7^th July 2007:

My hero was Don Given. I had a Don Given wall in my bedroom until Debbie Harry sang Heart of Glass on Top of The Tops.
He’s a gent.
Big Packie was asked to move by a lady on the go.
“You’d make a better door than a window,” she said.
Packie loved it. “Sure wasn’t it the ultimate compliment for a goalkeeper.”

The earliest occurrences of the phrase to make a better door than (a) window that I have found are as follows, in chronological order:

1-: From A Mingled Yarn (London: Richard Bentley and Son, 1872), by the British novelist Matilda Anne Mackarness (1825-1881):

In the large, comfortable room in the Priory, dedicated to the use of Dolly Masham, yclept the housekeeper’s room, sat Dolly herself before a table, on which were ranged some dozens of gallipots, filled with preserves, which she was tying down and affixing labels to, bearing the names of the different fruits contained in them. By her side stood Walter Ashleigh, with his little Skye terrier putting up beseeching paws for a further supply of pieces of bread dipped in the jam, which Walter had been for some time dropping into her mouth.
“Don’t, Master Walter,” cried Dolly, “you’ll make the dog sick; and you’d make a better door than a window, too,” she said, giving him a little push.
“What do you mean? Am I in your light?” he said, laughing.
“Yes; you’ve got so accustomed to stand in your own, I suppose, that you forgot how inconvenient it is, eh, Master Walter?”

2-: From one of the unconnected paragraphs making up the column Local Happenings, published in the Jetmore Reveille (Jetmore, Kansas, USA) of Thursday 7^th May 1891:

We learn that our nine have finally accepted the challenge from Marena and that the game will come off next Friday. As this will be the first game of the season, a large crowd of spectators will be there to hear that old chestnut “Down in front, you would make a better door than window.”

3-: From Sports and Pastimes. Notes by “Spectator”, published in The Kilburn Times, Kilburn News, Queen’s Park and Hampstead, Willesden, & North-Western Press, Marylebone, St. John’s Wood, Paddington, Kensal Green, Kensington, and Chelsea Advertiser (London, England) of Friday 31^st May 1895:

The secretary of the St. Pancras Cycling Club assures me that the proposed Vegetarian Club to which I referred last week, has no connection whatever with his club. This is news which I am particularly glad to hear and to publish in consequence of the similarity of the names. The majority of the members of that club look as though they live on something a trifle more substantial than nuts and cabbage. As a rule you can almost see through a real vegetarian cyclist, and I well remember how the wind used to whistle through me when I was speculating with my constitution in that direction. There was one advantage, however, I never used to take cold, you see I was so well ventilated. It’s a direct insult to a vegetarian to tell him he makes a better door than window. Besides, its [sic] a lie, to speak plainly.

4-: From The Dial-Enterprise (Boscobel, Wisconsin, USA) of Wednesday 11^th March 1896:

A lively crusade is on among the society ladies of St. Paul to abolish the big hats which have proven a better door than window for those in the rear, at the various places of amusement. Perhaps the men will not be obliged to go below between acts to such an extent as before.

5-: From Curative Powers of Concentrated Sunlight, published in The Chickasha Daily Express (Chickasha, Oklahoma, USA) of Tuesday 4^th December 1900:

“You make a better door than window,” is a common remark when a person stands in one’s light, but as a matter of fact the body is not opaque, as this rebuke implies. Artificial light, as the Roentgen ray, is passed through the body, and ordinary sunlight can also be so passed, as has been proved by taking pictures through the trunks of men. Interesting as this latter operation is in itself, it is still more interesting because it shows how that curative agent, sunlight, may be employed to kill not only bacteria which may be in the body, but various disease growths, such as tuberculosis and lupus.

6-: From The Otago Witness (Dunedin, Otago, New Zealand) of Wednesday 3^rd July 1901:

LARRY AND I SEE THE DUKE.

Dear Emmeline,—Oh, dear! It is all over! THEY have come and gone, and life is about as flat as a squashed beetle. That is rather an elegant simile, isn’t it? I heard a man in the crowd on Wednesday last use it, and it seemed too expressive to be original. Oh, that crowd on Wednesday! Larry and I took our stand against the railings in the Octagon at about 8 a.m., as we had spent our money on the evening show, and had nothing to spare for the mere morning affair. The day turned out to be a wolf in sheep’s clothing, for in spite of the dancing sunshine and the deceitful appearance of warmth, the air was bitterly cold, and we fairly froze to the pavement as we stood.
It was rather dull at first, with nothing to look at but moving masses of people (the majority of whom were anything but pretty) and nothing to comment upon but the remarkable solidity of the Balmoral Arch and the lavish waste of lycopodium in front of the pavilion. But we had a splendid view afterwards whenever we could get out of sight of our own luminous, pink noses, and the people in the enclosure, who had bought seats, condescended to sit on them—which was not often, though Larry told them quite politely when they first began to stand up that they would make better doors than windows.