Some of the places in Oxford we've eaten in and recommend.
For Lebanese, our favourite is Al-Shami, in Jericho.
Our favourite Italian restaurant is La Cucina, in St Clements.
Oxford has a lot of Chinese restaurants and we've tried a good few of them. Nothing stands out as exceptional, but our current favourites are probably the Oriental Condor (on Friedeswide Square opposite the Said Business School) and Koi (on George St), and for Szechuan food My Szechuan (in Gloucester Green). The yum cha (called dim sum here) is generally disappointing - there are several places where it's ok, but nowhere that comes close to Sydney or Hong Kong yum cha.
For Thai my favourite is the cheap and cheerful Angrid Thai, in Gloucester Green, and for Malay/Indonesian there's Makan La (on St Michael's), where I eat most Fridays with people from an Oxford Linux Users' Group.
For Japanese, Edamame (on Holywell St) has great food, but is quite pricey and only opens a few days a week.
For coffee, my favourite is the Missing Bean (on Turl St), though getting a table there can be impossible in term time.
For cheap and hearty vegetarian, the Magic Cafe (around the corner from us, on Magadelen Rd) is hard to beat, though a bit like a creche at times. The Gardener's Arms, in Jericho, is a good vegetarian pub.
Some places stand out for their ambience. The Vaults and Garden (under St Mary's Church) is a favourite place to take visitors in between sight-seeing. My favourite bookshop, the Albion Beatnik, does decent plunger coffee, and the Cafe Nero in Blackwells is ok too.
There are quite a lot of gastropubs around: the Magdalen Arms is one of our favourites, and not just because it's so close to us.
There are plenty of good Indian/South Asian restaurants. Our favourite is probably the Everest Nepalese, but we've been happy with all the Indian restaurants on Cowley Rd we've tried.