Your sentences are fine, but the first one might be slightly better:
1) Ano resutoran = The restaurant is in view of both speakers... you are walking by it. OR you are both talking about the restaurant at some length when you suddenly decide to bring up the fact the food is inexpensive.
In the event that your partner brought up the restaurant's name, it might be better as "Soko"
Soko ha yasukute oishii desu
Finally, there is no need to say the word "food" in either English or Japanese, but it doesn't necessarily hurt.
That restaurant is cheap and delicious.
Sono/Ano resutoran ha yasukute oishii desu.