This type of work is hard to do, so you must search on Bing to find a decent drywall repair company in Portland. Newspaper and Spackle used to be the way folks fixed a hole in the wall. The repair will fail in 6 months, so you will need to get it fixed right, and the best way to do this is by hiring a local dry Waller, like these guys.
Plasterboard or drywall usually comes in 12 foot or 8 foot sheets, but you can special order it in 14ft 6in sheets. Sound reduction could be a concern of yours and any decent Portland drywall company can point you in the right direction. 1/4″ drywall is not used that often, it is more expensive than 1/2″ drywall, and does not do well for sound reduction. These gypsum panels are going to be installed by the Portland drywall company, or you can do it yourself.
Portland, Oregon has a lot of homes that have plaster walls and ceilings. Along came drywall once they realized that they could save a lot of time and money doing it instead of plaster. The plastering process used to use wood, and when plasterboard was invented, it replaced it. Drywall will be used on your home if it is being built with modern building materials. Drywall does not crack as often as plaster does, so this is a big benefit.
Videos are great for learning how to install gypsum panels, but taping is going to take a lot more skill. A quality taping job is going to cost you, as the finishers that do the work earn a higher wage, but a Portland drywall company can match your job up with their skilled workers. You have to use tape on the joints so that they do not crack.