text inside <...> by me.
I thought that <greatest interceptor ever?> was the Spitfire or F-14
I hate to burst your bubble, but the F14 is more like an air-superiority fighter...
Spitfires and F-14 were both primarily air superiority fighters, but confusingly, the F-14 is also described as an interceptor in some contexts, and with good solid reasons, too. The main purpose of F-14 was being US Navy's number one air superiority fighter, everything else was extra.
If you want an example of an interceptor, Messerschmitt Bf-109 is quite good example from WW2 era. Of current fighter jets, most can be used in intercept roles, but F-14 was very well suited for the role because of its 200-km range AIM-54 Phoenix missiles, thus the dualistic classification as air superiority figher (because of excellent maneuverability) and interceptor (because of other attributes, mainly long-range air-to-air armament.
Practically, interceptor's definition requires interceptor to be able to swiftly engage targets on wide area. Naturally, speed used to be the single most essential feature in this role, but long-range guided missiles are nowadays just as important (or more important), and ability to carry a lot of them also means lot.
For example, F-14's effective area of fire was a 200-km radius, and its maximum speed was 2,485 km/h at high altitude.
F/A-18E/F, F-14's successor has corresponding specs of effective firing radius being 75 km (with standard AIM-120 AMRAAMs) and maximum speed of 1,814 km/h at high altitude.
F-22, a full-fledged air superiority fighter design, has an effective firing radius of 75 kilometres, or with AIM-120C-5 perhaps more than 110 km, still a lot less than F-14 with Phoenix missiles. Its maximum speed, however, is estimated 2575 km/h at high altitude (claim in Wikipedia based on test pilot's word, apparently, but naturally accurate specs are classified...); not that much more than that of F-14.
So, the F-22 flies about 100 km/h faster, but F-14 has 100 km more effective range of fire.
That makes the F-14 best interceptor of these at short notice, F-22 can very well fulfill the role as well... and F-18 will also get the job done well enough for most cases. Actually, for example F-15 would suit better for intercept role than F/A-18, but as said, all current fighters can and will be used on intercept missions as well as pure "dogfight" missions in case of conflict. And many countries are small enough (like Finland, having most important military targets on a relatively small area) that for example F-18 is more than sufficient for intercepting anything violating the airspace of the country.
...On the other hand, an airplane specifically designed for interceptor role, such as MiG-31, has effective firing radius of 175 km (with Vympel R-77M1) and speed of whopping 3000 km/h at high altitude, with combat range of 720 kilometres. I'm sure you can count the numbers together, in interceptor role this plane kicks some serious ass... on a short time notice. In longer run, newer planes will beat it because it runs out of fuel so fast.