Well, the 26" barrel won't be all that suitable for home defense OR target slugging - in your situation, I'd pick up a 20" smoothbore slug barrel - preferably with chokes and rifled sights - and plan on shooting fosters instead of sabotted slugs.... Sabotted slugs are pretty expensive to punch paper with - and I've seen a few smoothbore 870s that'd shoot either Sluggers or SuperXs pretty darn good - how's $6 for 15 rounds as opposed to $12 for 5 rounds sound??? That's the cost of fosters vs. sabotted slugs, respectively - besides, a decent smoothy slug barrel(non-choked) can be had for $50 to $100 used - you're typically going to spend atleast $200 for a fully rifled barrel... Lastly, for defensive purposes, a smoothy slug barrel cannot be beaten - it'll pattern some form of buckshot well, and handle slugs well, also... I use a fully rifled barrel and sabotted slugs for my dedicated deer gun, but IMO, that's about all they're suited for - I have other shotguns for defense, trap, and bird hunting...
If I was setting up ONE shotgun for everything, it'd have a 28" ventrib barrel with remchokes, and a 20" smoothy slug barrel with rifled sights, and remchokes - and I'd have IC, Mod, Full, and Superfull choke tubes on hand - I could cover all my purposes with such a set-up...
- georgestrings
PS - The Superfull would be for turkey hunting...