We've stayed near Bodmin several times and it's tricky to find anywhere really close, but you could try:
which we LOVED. Very special (two star michelin) if you can get in. Probably at the upper end of your distance preference....
Alternatively and much, much more casual, there are is a nice fun bistro much closer, in Fowey - although you can't book. You turn up and then have a drink and wait. http://samscornwall.co.uk/fowey/fowey-home/
Great atmosphere though and amazing seafood.
If you prefer to book and stay close there is the Fowey Hall Hotel, much quieter and mainly full of hotel guests. Easy to park etc. Still lovely though. http://www.foweyhallhotel.co.uk/food-and-drink
Have a lovely time!