in (western) Europe: YES to all of your luggage questions. Boarding passes depend on specific matching airline computer systems (and e-ticket difficulties)
'overseas' (from my point of view): luggage: it depends more on immigration rules/airport facilities (transfer facilities) than the airlines. Boarding passes depend on specific matching airline computer systems (and e-ticket difficulties). For concrete answers we would need concrete routings.
[This message has been edited by Rudi (edited 09-22-1999).]