The Scotch Opening
I think white has two alternatives only.
1) Nc3 or 2) Nxc6
I would play Nc3 in a game but it is difficult. Those who say open games are for amateurs are quite wrong these openings are as difficult as any others.
Ah yes the Steinitz. I love Sam Collins commentary about this line in his repertoire book. "This line is risky to the point of stupidity" 
Very interesting indeed I think that after 6) Be2 Bxc3+ gives black a better game then take the pawn after bxc3.
It's a great pity Steinitz cannot help us no doubt he had carefully looked at this exceptionally trick position.
Actually, instead of taking with the knight, don't take just yet, but move your bishop to c4.
I play the Scotch almost all the time, pretty successful for me.
This is just the main line.We have moved away from Stienitz. Black can avoid this line by 4) Bc4 Bc5 which leaves the game wide open. I must say again these openings are difficult when sharp lines are used .
Lev Gutman has authored a 200-page book on the 4...Qh4 variation. Faithful to his style, the book is chaotic, full with computer-generated random moves and very little to nonexistent prose.
The whole variation is very risky for Black, IMO Black's consessions are worth much more than a measly pawn.
Also, in the above variation of the "Scotch Gambit" (actually it's not really a Scotch Gambit) instead of 6...Bc5 Black can play 6...d5! and White is playing a well-known variation of the two knights defence where he has commited himself to 0-0 sooner than desirable (hes has not enough time to control the critical d4 and c5 squares).
With the rest - in the scotch gambit line no-one will play Ne4 OTB, everyone will automatically play d5. Despite whan Roman may say on his DVD's these lines are very comfortable for Black as long as he knows some theory - indeed if he plays the Qh5 line then if anythign White is the one struggling ot hold equality.
Nutty