Non Residents can not take a car on Iona. There is no direct connection from Oban to Iona. However, you can do walk on the Ferry to Craigmore Terminal on Mull, then walk to Terminal, catch bus to Fionphort Post Office, walk to Mull Ferry Terminal, take Mull Ferry to Oban Ferry Terminal. ride bus around Iona. Reverse trip back. You may have to buy a ticket for each portion, or check to see if there is a Scottish Transit Pass available that would cover you. Or Book a Day Tour. Look at Visit Scotland Web Site. You can drive over bridge to Skye. If you plan to stay on Skye book well in advance. You can stay in Ft William and drive to Skye as a day trip. Having been to Scotland, I understand that you have to see the "Highlands". Since you are interested in History, you may want look at which periods interest you. The Middle Ages had a lot happening in the South nearer the Borders with Castles and the Abbeys. The Rennaissance, with Mary Queen of Scots, in Lithinglow, Edinburgh, Sterling, etc. "1745" Culloden in the North. Be sure visit Loch Ness so you can call up Nessie at Urquart Castle. How much time do you have?