The Legend of Zelda: A Link to the Past menu problem

Hello everyone,

I'm new to game emulation and recently downloaded one of my all-time favourites The Legend of Zelda: A Link to the Past. The issue I am experiencing is a little annoying, when I press the Start button it loads the Item screen, from where I am able to select any item I need i.e. Hookshot, Boomerang, Bow etc... There's also a Do screen underneath the Item screen from where I should be able to select items such as the Pegasus Boots, Titan's Mitt, etc...However, I don't seem to be able to select anything from this screen and therefore am unable to use any of the items. I hope this makes sense. I've tried pressing the L and R buttons to no avail.

Please can someone help!