Developers tend to be directed at one specific area of development - contrast, tonal range, acutance, speed, grain size. Going for one area tends to mean loss in another. For example, a developer could give you excellent tonal range with reduced grain but you lose film speed.
Choosing a developer means deciding what qualities are important. If you are not sure then choose a good general purpose developer that compromises on all areas.
The best I can recommend is D-76 (which is virtually the same as Ilfords ID-11). This will cope with most films and give very good results - and it is very forgiving.
I am sure, though, that people will wade in with their particular favourite. Mine is Microdol-X. But like so many things in photography it is purely personal.
Start with D-76/ID-11. ;-)