Ok, I just looked into these...the only customizable features are guard, grip, grip color and pommel. They have only the one blade size and type. So it'd be a semi-custom sword...for the money, it isn't bad. 42" overall means the blade is or will be about 34" in length...this is about the outside edge of where their blades transition from flexible to wippy.
Ulrich, for the Crusader period you're looking to emulate (I'm thinking pre-3rd Crusade) you'll want a single hand sword; might be long bladed like Deus Irae (that's what I named her, you'd know it as the ARN sword) although for your height and size, you probably won't want that. A singlehand sword with an overall length of 36" (30-32" blade) might suit you best. Long blades do look nice, but they can also be unwieldy when drawing or sheathing the blade, especially if you have short arms. Deus Irae is a little long even for me...but it'd be a cinch to draw from the saddle, should I be so lucky.