Racing on a Touring Bike/Touring on a Racing Bike

I've been bike shopping, and I have been thinking about how I am most likely to use my bike.

I'll be training on it, of course, and racing when the day comes, but I also want a bike that will be comfortable and fun for tooling around the neighborhood with my kids, riding to work when the weather is nice, etc. I get the impression that a "real" road bike might not be the best thing for such non-competetive pursuits. I really can't afford to buy two bikes for different purposes. I've found categories like "Comfort Road" (Trek) and "Sport Road" (Cannondale) that seem to strike a compromise between comfort and performance. Does anyone have any advice/experience/insight?

Thanks,

Tim Edwards