How much should one spend in order to enhance Shabbos and what should be part of the Shabbos menu?
The foods eaten to fulfill the mitzvah of Oneg Shabbos vary in accordance to each countries definition of a luxurious food. Thus those foods and beverages which considered delicacies in ones area are to be eaten on Shabbos.
Meat and wine: Although there is no obligation to specifically eat meat and drink wine on Shabbos, nevertheless since in general most people have greater pleasure in consuming meat and wine over other foods and beverages therefore they are to increase in eating meat and drinking wine in accordance to their affordability.
Fish: Eating fish is included in the Mitzvah of Oneg Shabbos. In the times of the Talmud Oneg Shabbos was fulfilled through eating large fish. Fish should be eaten in every meal, unless it is hazardous for his health or he despises eating fish to the point that he does not receive pleasure in eating it but rather pain. It should especially be eaten by the third meal.
At the very least-two cooked dishes: Even one who cannot afford to buy many varieties of foods for Shabbos, nonetheless it is proper to beware to have at least two cooked foods [by each meal]. [This applies for the first two Shabbos meals but not for the third meal, in which case having less than two dishes suffices. If one generally has two cooked dishes for his weekday meal then he is to increase on Shabbos and have three cooked dishes. If one is accustomed to have three cooked dishes during the week he is to have four on Shabbos.]
Increasing in ones Shabbos expenditure-making many dishes of foods: Besides for the basic Shabbos foods listed above, whoever increases in his expenditure of Shabbos foods [and other Shabbos needs] in accordance to the amount he can afford, is praised. The money spent for one’s fulfillment of Oneg Shabbos is not included in the budget decreed on Rosh Hashana.
List of the basic foods that are to be eaten during the Shabbos meal:
- Meat and wine
- At least two cooked dishes.
- Increase in foods as much as one can afford.
If one has a dislike for meat and wine must he nevertheless make an effort to eat it on Shabbos?
 Thus in such a case he should not eat fish, as Shabbos was given for pleasure. [ibid]
 Siddur. Sefer Chareidim [chapter 33] states it is a mitzvah to eat fish by all the meals, especially by third meal in order to elevate the souls that have been reincarnated into the fish. In the writings of the Arizal it is taught that the souls of the Tzadikim are reincarnated into fish. [See Piskeiy Teshuvos 242 footnote 63] In Kuntrus Achron 242/4 Admur mentions an opinion which rules that eating fish on Shabbos is a Biblical command. However Admur rejects this ruling saying there is no legal basis to say that the Sages instituted specifically fish to be eaten.
 Lit. Tavshilin. This refers to two cooked foods. [see Peri Megadim 242/1; 527/12] As for the definition of cooked foods in this regard the Peri Megadim [242 A”A 1] refers the reader to chapter 627/3-4 [Admur 11-12] in which the definition of Tavshilin, cooked foods, is discussed regarding the Mitzvah of Eiruv Tavshilin. There cooked foods are defined as follows: Any food which is cooked, fried, baked, pickled and is eaten together with bread is defined as a cooked food. Thus one may use meat, fish or eggs. A raw food is invalid.
 Nimukeiy Orach Chaim 242
 Kaf Hachaim 242/9
 So is implied from Admur’s wording of Shabbos expenditures and making lots of foods.
 As there is no obligation to eat specifically meat or drink wine on Shabbos, and since to this person eating or drinking the above is not enjoyable, he does not have to make an effort to eat or drink it.