Backstreets offers all the standard Italian fare you'd expect, but their focus is decidedly pizza. It's some of the best in Blacksburg -- really fresh ingredients, good crust, sauce not overdone (and an excellent flavor). They also do delivery (of all their foods, not just pizza), and their prices are competitive with the largest chain restaurants (but higher than some of the college-crowd delivery places), especially if you watch for coupons.
My favorite way to enjoy Backstreets is at the all-you-can-eat lunch buffet on weekdays. It's reasonably priced and they have a great selection of vegetarian, meat, and mixed pizzas, plus a pasta of the day and those powdered sugar encrusted, fried pizza dough balls. It's a great place to bring kids, as the atmosphere is decidedly informal, so no one minds kids' chatter or a bit of wiggling. And they eat cheap (or even free, if they're young enough) from the buffet, so they're a bargain.
If you're not in the mood for pizza, it's still a good choice for a casual dinner out; I can vouch for the calzone and some of their pasta dishes (and you'll go home with lots of leftovers from both). They have a reasonable children's menu, too (one that can be scribbled on).
It's right downtown and their lot is small, so sometimes you have to walk a block or two, but usually you can find a close space. And they have an outdoor area that's nice and breezy all summer long.