I suggest that you stop in at Multnomah Falls Visitor Information Center to see if any are having trouble (like a downed tree or washed out bridge) at your hike choices. The Volunteers there are knowledgeable and get updates from the Forest Service.
There are a lot of hikes depending on what you like. Some that I like and know others who volunteer in the area are: Do be sure and check with M.F. on the safety of Oneonta because I don't know when you are visiting. It may be slipppery.
.Tamanawas Falls (a short 2 mile in the Mt. Hood District just past Hood River on Oregon 35) Tamanawas is a great place for a picnic.
Beacon Rock is a volcano tip (very dormant) by Bonneville Dam on the Wasington side. It's criscrossed with switchbacks to the top Nice views and not everyone can say they climbed to the top of a volcano... Unique history, ask a volunteer at Muntnomah Falls about it..
Lauterall Falls on the Scenic Byway out of Troutdale on Exit 18.
Check out http://www.nwkiker.com and use the search features like: Feature, Difficulty Level, Aphabetical search. Also, you can go from search to search by clicking on next or previous. Online, this program shows Oregon, Idaho, Montana, and Washington. They have CDs available for the Gorge area for sale in the gift shop at MF.
If you have any problems with the search features or questions, you can PM me.
Edited: 4:51 pm, February 20, 2012