Smithfield is bit hit and miss, on my last visit I was served rather flat hop ale and other ales was sold out and on better days, it can be really good.
Alex - Great pub shame about opening hours.
Flowerpot - One of true gem in Derby. I had pint of their famous Imperial Stout (10%) very dangerously drinkable. I had 3 pints and was already legless..
Olde Dolphin - Oldest pub in Derby. Lets hope you are not tall.. beware of low celling.
You should add Babbington Arms, I know it is JDW BUT they do serve excellent real ales, ciders and bottled real ales.
And..
My favourite pub of all.. Brunswick. Ohhh I was so hooked drinking its own brew that I wanted to move in! You can see brew being processed in one of room (Flowerpot also have one)