There's not a great amount to see in the city - there's a rather large castle on a hill next to the city centre (Špilberk Castle), which boasts a decent set of walls and the deepest well in the Czech Republic. The city centre itself also has some wonderful old-world buildings, but apart from that there's not a large selection of typical tourist attractions.
A wonderful clock stands in Brno's centre square, however - the city has a historical legend about a general who made the city's clocks chime noon at 11am to fool an invading army, and the chronometer stands to represent the city's association with this trick and the "Brno Noon", which is of course at 11am. It's a reasonably large sculpture shaped rather like 30 St Mary Axe ("The Gherkin") in London, and the top rotates to tell the time.
There are some seasonal attractions as well, such as the firework competitions during the summer, and if you have access to a car there are apparently some nice castles in the surrounding countryside.
The cost of food and drink is very reasonable - beer is particularly cheap and plentiful (as it was in Prague) so if you like the local beer you'll be well satisfied. Typical meals run from 120 - 200 CZK (£4-7 or $6-10) and a drink is around 25 CZK (£0.80/$1.20).
On the topic of food, Czech food is really delicious (so long as you're not vegetarian, that is). Generally it consists of large amounts of meat, copious sauces, and an abundance of cream all combined into one dish, something which I can really get along with. It's a shame that Czech cuisine is harder to find in other countries - I'll have to try hunting down some in London.
The level of English comprehension seems to be alright - there was usually one or two people in the restaurant or shop who would understand you, and a decent amount of signage (especially tourist signs) are in English as well as Czech.