It's hard to beat a good .357 for a first centerfire gun. Like somebody mentioned already, everybody should have one of these in their collection.
A 4" GP 100 (stainless would be my choice) will give you a lot of versatility and it's durable enough to last a few lifetimes. I bought a 4" SW 686 as my first revolver and I've never regretted it, that gun has been used for anything you can think of (concealed carry, hunting and hiking, home defense, etc.).
Now hatred is by far the longest pleasure;
Men love in haste, but they detest at leisure.
- Lord Byron (George Gordon Noel Byron), Don Juan
(canto XII, st. 6)