Actually, "Old School Top Gear" would be the old Top Gear series. It ran from around '77 to the early 90's and was really boring. It didn't have Clarkson or anything else in common with the current Top Gear.
Clarkson showed up around then, and it became much more interesting. But he left in 1999, and as a result the BBC started Fifth Gear, which is still around.
In 2002 the current iteration of Top Gear began, with Clarkson, Hammond, and Star in a Reasonably Priced Car. May came on to replace some guy I can't remember in 2003.