Portsmouth - parking and meal question

Mods, I'm not sure where to post this, so move it if needed.

I am driving to Portsmouth on May 5th to see the Rhydian concert at the Guild Hall. I plan to arrive around 3:30 for a 7:30 show.

Any ideas where to park and then get a not too expensive meal, hopefully without having to move the car again? My friend is not keen on Italian.

My friend and I are fine with walking a reasonable distance but would prefer to be fairly close to the Guild Hall so we don't have to walk too far to our car after the performance.

Thanks for any reccomendations.

http://www.welcometoportsmouth.co.uk/portsmouth%20carparks%20map.html

Here's a map, showing the car parks in Portsmouth. The one next to the railway station is about a two minute walk to the Guild Hall. There are many inexpensive places to eat on Commercial Road/City Centre. Hope this helps.

I think there's a multi story by commercial road which is a short walk from guild hall...

Thanks, this has been very helpful.