There are 32 sports at the summer olympic games, with (if my calculations are correct) 283 gold medals attributed to the following categories (men's + women's combined) :

Aquatics (total = 46 medals)
- Swimming : 26 individual + 6 team relay medals
- Synchronised swimming : 4 medals (women only)
- Diving : 8 medals
- Water polo : 2 medals

Archery : 4

Athletics (total = 46 medals)
- track : 23 medals
- jumping : 8 medals
- throwing : 8 medals
- road : 7 medals

Badminton : 5 medals

Baseball : 1 medal

Basketball : 2 medals

Boxing : 11 medals (men only)

Canoeing : 16 medals

Cycling : 6 medals

Equestrian : 6 medals

Fencing : 6 medals

Football : 2 medals

Gymnastics : (total = 18 medals)
- Artistic : 14 medals
- Rhythmic : 2 medals (women only)
- Trampoline : 2 medals

Handball : 2 medals

Hockey : 2 medals

Judo : 14 medals

Modern Pentathlon : 2 medals

Rowing : 14 medals

Sailing : 11 medals

Shooting : 16 medals

Softball : 1 medal (women only)

Table Tennis : 4 medals

Taekwondo : 8 medals

Tennis : 4 medals

Triathlon : 2 medals

Volleyball : 2 medals

Weightlifting : 14 medals

Wrestling : 18 medals


Most difficult medals to get

The most pretigious medals considering the number for each sport, number of participants and number of matches would be the team sports with only 2 medals (men's and women's), so :
- baseball/softball, basketball, football, handball, hockey, volleyball.

Then come the individual or double sports with tournament style matches :
- tennis, table tennis, badminton

The following sports have more than 10 medals each :
- aquatics (46), athletics (46), gymnastics (18), wrestling (18), shooting (16), canoeing (16), rowing (14), judo (14), weightlifting (14) and sailing (11).

What country excels in what sports ?

Here are the results for the most popular sports at the Athens 2004 Olympics for the events which are complete.

Swimming

1) The US got 12 of the 32 (37,5%) swimming gold medals, and 28 out the 96 (29%) in total.
2) Australia got 7 (21,9%) gold and 15 (15,6%) in total.
3) Japan got 3 gold and 8 in total.

Shooting

China ends first for golds, with 4 medals out of 16, and 9 medals in total out of 42.
Russia comes 2nd for golds, with 3 medals, but ranks first in total with 10 medals.

Rowing

Romania get 3 gold and nothing else, then Germany comes with 2 gold and 2 silver, and the UK with 1 gold, 2 silver and 1 bronze.

Judo

Japan dominated, taking no less than 8 gold out of 14 (57%) and 2 silver. No other country managed to get more than 1 gold medal. China got 5 medals i total and Cuba 6 but no gold.