Wolverine is pretty good, although the first ones aren't all that great. The repetetiveness kicks in if you read too many in a row though.
Several episodes are tied in with the Uncanny X-Men, logically ofcourse.
I only cared for the first of Cable, never liked X-Man; X-Force is interesting, they added Sabretooth to the mix there after a bit (or rather, shortly before they ended the series or switched to Force-X I believe), always fun.
The Sabretooth standalones are nice.
Watchmen is always good, although it's only one fairly short series, it doesn't read all that fast.
As for European comics, there's always "Lanfeust", "Lanfeust of Troy" is the first series, "Lanfeust of the stars" is the current one, by Arleston and Tarquin. Especially the first series is quite hilarious, the sequel series are a bit boring. Not comparable to marvel comics ofcourse.
If you care for the borderline vulgar (or not suited for kids whatsoever), try finding some Froideval. Chronicles of the Black Moon has an excellent first 12 parts, after that apparently things turned rather bad. (haven't read those though, the publisher is borderline bankrupt and there are no Dutch translations as yet) 666 is filled to the brim with sex, but also hilariously absurd (the daughter of the Devil is trying to conquer earth, only one truly blasphemous priest stands in her way).
Largo Winch by Vanhamme isn't bad, uncomparable to the rather forgettable tv series. Also by Vanhamme is "The Chninkel" along with Roszinski. That one got voted as the best Belgian bande dessinné a while back, definitely amongst the best. Also more adult oriented, kids will only get depressed by it.
Those two also created the series Thorgal. A story about an outcast in Viking times, mostly due to the fact that he was an orphan, found at sea as his parents died crashing on earth with their spaceship. A fairly special setting, but especially the first were very good. Untill recently when others took over and did a sort of spin-off.
There's also the series Storm. An astronaut returns to earth to find that he was thrown in the future and the earth is desolate, no oceans. Again, mostly the first ones that were good.
The French artists Mézières and Christin have another great series "Ravian". It starts with the tales of a young guy, member of a time agency sometime in the future, but it evolves and has remained a great series, even after 35 years. (heck, the first ones weren't the best, it really grows as a series)