Nice lookin' bow. I think those Shakespeares are some fine bows for the money.
Looks like it probably is a 42# bow.
Take the string, pull it tight and measure it. Then get another string.
Unless it is to be used for a fishin' bow I'd leave the no gloves off, the rubber thingys.
I'd try an 8" brace height and go from there. Change it about 1/4" each way till you find the "sweet spot".
For arrows I'd go wit some GT 35/55s. I start with a 125 grn. tip and leave the shafts full length. Cut them as needed for the correct spine, being long is fine. The shorter you cut them, the stiffer they'll be. To weaken 'em add more weight up front.
Good luck, and have fun..