In Guildford itself not much
I would suggest William Bray in Shere (Shere Drop or Ranmore Ale) or William IV in Little London – EDIT: I saw you said dinner, food pretty good at William Bray. If you are eating in Guildford itself a pub with a beer garden in the town is a bit hard to find, really just a few pubs with outdoor seating/benches. I would suggest either White House or Weyside both by the river.
Shere village church would worth a quick stroll around, ducks on the river. All very picturesque. Used in quite a few films, eg Bridget Jones. Used to be on my xc loop and/or a ride to Peaslake for S/H
EDIT2: Percey Arms I have eaten at many times, not really that memorable to be honest