Verona is warm, elegant, welcoming -- easily toured in a day; or a wonderful city to live like a local for a week.  Beware however of VinItaly; an annual international Italian wine exhibition--the largest wine show in the world. 

http://www.vinitaly.com/visitatori_en.asp

If you are not attending the show, which for 2009 is April 2-6, you do not want to be in Verona on these dates.  The throngs of people are overwhelming, particularly in the evening when the "fiera" is closed and the showgoers flood the downtown areas and restaurants, especially Bottega del Vino, which overflows into the streets.  Not that VinItaly is a bad thing, it is actually amazing, but not recommended unless you are attending with someone affiliated with the wine industry or some other arranged tour.

The main tourist and shopping areas are easily accessible on foot.  The streets are cobblestone so mind your footwear, particulary in the rain.  If you are arriving by train or from a hotel not in the center of the city, tell the taxi driver, "a centro" (ah chen troe).  He will deposit you at the taxi stand in the Piazza Bra, near the  Arena di Verona,   http://en.wikipedia.org/wiki/Verona_Arena .

Tour the Arena first, then play tourist and stop for a coffee at any of the cafes near the Piazza.  Proceed then to the area pedonale (pedestrians only),  (the Arena will be on your right, the Piazza behind you). Wander at your leisure, stop by the Casa di Guilietta if you must and continue until you find the smaller Piazza and the location of the outdoor market.  Some of the stalls are permanent, but I think otherwise Wednesdays and Saturdays are market days and you will find fresh produce and other Italian market treats. 

Many of the smaller stores still close in the afternoon from 1pm-3pm (approximate) and many are closed on Sundays.  

Buona giornata!