Not a topic I usually get into, but I have some time this morning.
I own a 22-250 and a 220 Swift - the 22-250 is not to be sneered at - but the Swift is a better rifle if you go the 22 cal route - but is really only optimized if you hand load with a premium bullet - deadly on deer (also illegal in most of Canada - I am now more law-a-biding) and I am sure used properly it would do a fine job on hogs - but it would not be ideal.
25-06 would do a reasonable job on hogs - especially with a fairly solid cored bullet - but is a deadly coyote and deer calibre - just do not plan on using the hides of any dog you shoot. I have taken the largest Alberta deer at long range with 110 grain ballistic tip bullets traveling at around 3600 FPS - and they do not go far when you tag them.
My absolute favourite - for all North Amrican animals was once a wildcat round but can now be bought off the shelf - so no re-loading is required. 338-06
Hand loading allows me to take bullet performance way up - or bring it down for smaller game.
That is a 338 cal round placed on the front of a 30-06 cartridge. There is nothing in North America that can stand up to it - shoots soft - my 105 pound wife uses it herself - and it is cheap to shoot if you reload.
For a straight "buyer of guns and ammo" - in other words no reloading - the 308 has done the world a pile of good service and I personally have taken many large bears and moose with it in northern Canada. You can find everything you need in almost any hardware store if you are out in "small town" country and no where near home.
Despite all the discussion of firearms, the all time and probably one of the best all round long gun and cartridge combinations is the venerable old 30-06. You can never go anywhere and not find a gunsmith who cannot fix it, a store that does not carry the ammo and so on. It too has taken everything North America has to offer and done it with ease. I believe people ignore it because it is an old rifle and has lost the mystique of something fancy - it is no longer marketed as a sexy rifle. And it is not a boom stick cannon - it is simply a good working rifle. Always look here when you consider a good all round rifle.
In the end I could go on for a long time - the following are the two most important items for anyone using a long gun.
1. Put some decent glass on top - spend as much or more on the sights as you do on the rifle - especially if you plan to do any long range shooting. You will not regret it - even as you grit your teeth paying for the glass!
2. Shoot it lots - learn how to clean it properly - build up of copper does not come out with an oil swipe - and tune the rifle and the trigger. Store bought equipment is usually only fair. A good smith with help you if you do not know how to do this yourself. It will cost, but in the end you will be very, very happy you did it.
Heck - buy two rifles! One for dogs and one for hogs. And some re-loading gear. Two rifles allows you twice the fun and the re-loading equipment allows you to build a tack driving round. You have no idea how accurate a Swift can be at 400 yards plus when rounds leave at nearly 4000 FPS.
For almost all of the above systems I have mentioned - with my reloads - for hunting in the field - not target shooting - I sight in 3 inches high at 100 yards - allowing me to "hold on fur" out to about 300 yards - knowing full well that my round - all things being equal - will hit slightly above, on, or slightly below the aim point - depending on the range - making my shooting easier as I do not have to guesstimate the bullet drop for longer ranges. Especially when I am in a situation with no rest and no time to think about the shot.
Finally - if you are in the desert and making some long open area shots - buy a Harris Bi-Pod - get the one with the short legs - you will use it every day.
Have fun
Bez+