In Switzerland, the majority of interned foreign soldiers had to do hard work, for example in road construction or agriculture. Apart from that, they were generally treated well. (One has to keep in mind that almost every Swiss man served in the military during the war, so the lack of civil manpower had to be replaced somehow.)

The conditions for American airmen on the other hand were much better since their embassy paid for mountain resort hotel rooms and catering.

All in all, Switzerland interned 104,000 foreign soldiers:

34,500 French, 24,400 Italians, 17,100 Poles, 7,200 Germans and Austrians, 5,800 Britons, 2,100 Yugoslavs, 1,600 Americans and 8,400 Soviet citizens.

Not accepted were SS-members and certain foreign troops under German command like Vlasov's army.

Source: Historisches Lexikon der Schweiz.

[Edit] News article "Polish soldiers became 'Swiss' construction workers", including picture gallery.

Ireland operated a double standard regarding internment. Officially any air crew who crashed or landed on " operational" flights were interned but those on training or traveling to another location were repatriated. Of course in practice only Allied flights were likely to be of the latter sort and their crews were briefed to claim to be on training missions.

Internees at the Curragh in County Kildare were treated much better than IRA members who were detained in an adjacent camp. They received an allowance from their government for civilian clothes and parole extended to the neighbouring towns. The German internees began to have financial problems later in the war as their legation ran out of money.