Wear whatever you want. Tartan encouraged! Even if it's just one sock.
Short answer: Glasgow is the largest major airport, although Edinburgh and Inverness are also options. it's a 5-6ish hour drive to Skye. Highly scenic. Not one you'll forget in a hurry.
Yes. There really is no way around it :)
Greshornish is a traditional white manor house that sits on a beautiful secluded peninsula. Joyce Holloway says the single track road is a wee bit bumpy. You can learn more about it here: greshornishhouse.com