Canoe / Hike

The Buffalo River of Arkansas fits your description pretty well. Its a fun river with good fish, scenery, and camping. We did 3 days there last year and really had a great time. We did not do the trails but I know there are lots of good trails in the area too. Really, the river was so nice, it was hard to talk ourselves into a trail.

Canoe rental is plentiful and there is really nothing more than class 2+ on the river.

I think the boundary waters (BWCA) would fit the bill nicely. You can rent canoes in Ely, MN.

Sylvania Wilderness in the Ottawa National Forest (UP of Michigan) is another good option much like the BWCA though scaled down a bit and less developed so you may have to drive a little ways for a rental canoe.

With the boat ride, Isle Royale would probably end to far out of your driving requirement, but it would be something to ponder.

Any ideas for something further west? I've always wanted to do a Colorado or Wyoming trip.

+1 on the Buffalo River idea. I have been all over the US and I cant get enough of the Buffalo River. Lots of mountain creeks for water, cool hikes, the tallest waterfall between the Rockies and the Apps (Hemmed in Hollow). Trails that go into caves, big bluff/goat trail/ Hawksbill Crag, Lost Canyon, Indian Creek, Eye of the Needle, the only Federally protected ex- Gold Rush town (Rush) is on the trail, the Buffalo River was the 1st Federally protected River in the U nited States and for good reason, by all means consider the Buffalo River.