What price romance? Does it matter? Old Angler's Inn serves better food than it needs to, under the circumstances, because this century-old inn is endowed with a dim and cozy lounge where you can sip before the fire on a deeply cushioned sofa and with a shaded terrace at the edge of the towpath. In warm weather it is the perfect stop for bikers, hikers and fitness-pretenders, who can reward themselves with a cold beer and a platter of smoked trout. On winter evenings dinner is compelling, ordered while you relax in the lounge, eaten in the dining room up the narrowest winding staircase outside of the hold of a submarine. The prices are high but not astonishing (except for some of the wines), and the food is reasonably good, sometimes better than that. At dinner, the rack of lamb has stayed consistently fine over the years, and seafood dishes tend to be satisfactory. At lunch the seafood salads suit the outdoors and are fresh and agreeable. Furthermore, this year the interior has been spruced up, so the Old Angler's is more pleasant than ever. 10801 MacArthur Blvd., Potomac. 365-2425. L $6.50-$13.50, D $13.50-$19. L, D daily. Closed Mon. AE, CB, DC, MC, V. Res sugg. Full bar.