British -
the twenty-fourth of August nineteen ninety-seven
the sixth of June two thousand and three
May the 10th two thousand and one
two thousand and three o two twenty-nine OR two thousand and three two twenty-nine
Writing the date this way round in Britain is unusual in normal circumstances.
29-02-2003 would be - twenty-nineth of the second two thousand and three.

AE
May 10, 2001
"May tenth, two thousand (and) one"

BE
24 August 1997
6th June 2003
(see #1)

AE
2-29-03, 2/29/03
"two twenty-nine oh-three"
2-29-2003, 2/29/2003
"two twenty-nine two thousand (and) three"

BE
29-2-2003, 29-2-03 (?)

German
2003-02-29

Please don't use this form except in exclusively numeric contexts such as computer programming. In normal English, the year does not come first, and we do not use a leading zero before the month or the day.

I would like to know
whether you should use st,nd, rd and th
with dates (written language)
or do you use the abbreviations only in the spoken language

is this the american way of writing a date 23/9/2004

and

is this the British way of writing a date 23.9.2004

this means
slashes in AM E
and
dots in BR E

is it possible to simplify it like that

(There are really a lot of threads in the archive on this; did you try Search all / Suche in allen Foren?)

When the date includes the year, writing the ordinal ending is wrong in AE, optional in BE.

AE
May 10, 2001
(pronounced "May tenth"; but writing *10th would be wrong)

BE
10 May 2001
(also sometimes:) 10th May 2001



When the year is not mentioned, it's optional.

AE
The meeting is scheduled for May 10 / May 10th.
(both pronounced "May tenth")

BE (?)
The meeting is scheduled for 10 May / 10th May.
(both pronounced "the tenth of May")

However, note that the ordinal ending is not more formal or more correct; if anything, it tends to look a little less formal or businesslike.

Summary:
Writing out the ordinal ending is never required.

re #4:

Yes, slashes are typical in AE, and dots are not very typical in AE (except in frou-frou ultramodern typography), so they may be more BE. As far as I know, hyphens are acceptable in either.

The order you give is wrong for AE, where we always write the month first.

thank you very much

hm -- us's remarks on dots are true for BE too. BE like AE normally use slashes or hyphens.

use -> uses