Aimsmum, one thing you might want to do is go and see Another Place, the Anthony Gormley installation. Now it's not in the City Centre, it's two or three stops out on the train, but it is worth it. Especially if the weather is as nice as it is today!
Another Place .
There has been a battle to keep the installation where it is which has finally been won, although I think they have to remove some of the statues for safety reasons.
In terms of pubs (rather than bars), two of my favourites are the Jacaranda on Slater Street (L1 4BW if you want to multimap it), Thomas Rigby's (L2 2EZ) which serves some gorgeous real ales and continental lagers. I used to love the Picket on Hardman Street but I think it closed down a while back now.
If you're going to the Anglican Cathedral to see the view, on the way back you could do worse than pop to the Pilgrim, on Pilgrim St (L1 9HB), another lovely pub.
(Please bear in mind I'm remembering most of these pubs from student days so they might be a bit studenty...)
HTH and hopefully there will be someone else along who can tell you about all the clubs, not been clubbing in many years myself I'm afraid!
Better go it is my dh's birthday today and we're having a mad one... er, staying in with a takeaway and a DVD!!!