We love, love, loved our Chicco Keyfit 30 infant seat! Easy to install correctly (take it to a seat checkup anyway), baby was comfy and great colors. It also was one of two, top-rated infant seats in Consumer Reports.
Before you buy any seat, ask the store to allow you to bring it out to your car and install it there to make sure it fits properly (they'll probably allow you to do that if an employee goes along with you). Most stores DO allow it.
re: the Britax Companion that Lisa posted about above me, I'm almost positive the bar she's referring to is called an 'anti-rebound bar' (popular in Europe) and it serves to anchor the infant seat against the car's seatback in case of a crash (not really to do with protecting their feet).