I'm currently doing a RTW flight in a Maule in FS. I'm at least a month from having to cross the Atlantic, as I'm following the coast. Started at Millville, NJ, hope to end there too, but unless I figure out a good way to fly over the ocean I might end up like those Avengers off the Florida coast. When I eventually get to England, after going down the east coasts of North and South America, then up the West coast to Alaska, then down the east coast of Asia, along the Indian Ocean, down Africa, up the other side, and possibly a diversion to visit my future home of 6 days in Bremen, I was planning on flying from the north-western most airport I could find to the closest airport in Iceland, the across to Keflavik, then on to Greenland. Is this the best way to do it, and without using GPS is there a reliable, accurate way to fly from Scotland to Iceland without ending up over the north pole?

Plan it as a straight line in Flight Planner, take up the heading specified, and hope for the best. I'd suggest tracking a VOR or NDB outbound initially to make sure you're correcting properly for wind. Iceland's pretty big; should be hard to miss. Greenland's bigger still...

Unless you've added extra fuel tanks to the model or are using "Unlimited Fuel", you may not have the range, though...

I assume you use only default scenery... which makes things a little complicated concerning the distance between the airports there as MS forgot about 80% of them

Only reasonably route with default scenery is to follow the transsiberia express route.

As i have scenery for most of the major airports in russia, i can't give an exact route...

Places you'll pass through are
Novosibirsk
Irkutsk

The following ones are the full route from Chita to Alaska, using only default airports
Chita
Blagoveschenk
Khabarovsk
Yushno-Sakhalinsk
Petropavlovsk Kamchatka
Attu

Alternate is to Gambell(starting from petropavlovsk)
Petropavlovsk Kamchatka
Anadyr
Providenya Bay
Gambell
This alternative can only be used WHITOUT simviation mesh scenery, as there is a major bug near Anadyr that causes the sim to crash

Only problem with going throug Russia is that you are range limited to 850NM... longest hop (Yuzhno Sakahlinsk to Petropavlovsk Kamchatka) is close to 1600NM.

Best alternative is going south, follow the cost in Iran and Pakistan, then go as close to Nepal as your aircraft can manage and then through Myanmar and Thailand. When you reach the pacific, go north and follow the coast until you can get over the pond to Japan. Go north to Yuzhno Sakhalinsk and then continue on the route i showed above.

With 800NM range you won't make it past Gambell (or Attu), and not through China unless you install some addon airports.

For china it's quite easy, get the latest 'China Airports' package from avsim.com (Winfried Orthmann), which will give you some extra stops throughout China.

Russia is a more complicated affair, as it needs a lot of work to get it right, and you'll need to be able to read some cyryllic and have some experience in scenery installing.