Haven't done Russell, but I like your other choices! We're kind of in similar boats on this, I think.
Mt. Hoffman, on the way to Dana, is a great hike with phenomenal views.
Dana is a great day hike, but it is a little tougher than White, in my opinion. (Did it for the first time in 2012, trip report
here .) White is walk up a rocky jeep road, while Dana is use trails that get pretty steep and rocky toward the summit pyramid. The only thing that makes White potentially tougher is the altitude.
I'd hate to do White and miss out on the Ancient Bristlecone forest right before the White TH. I think you might find White a little boring.
Langley is superb (did it first time in 2012, see trip report
here .)
If it was me, with your time frame, I would do (1) Hoffman, (2) Dana, and (3) Langley. Good acclimatization plan, less driving (more direct route), great views. Not technical, though, in less you make it so.
Saw Shasta mentioned above too. Different type of experience (see report
here). Gotta say, for a relative newbie like myself (first 14'er back in 2010, first mountaineering experience in 2011), Shasta takes it to a different level in terms of strenuousness and technical ability. Hardest climb I've done yet. Beautiful views but some real tedium on the climb. Not really a day hike (though it is often done that way by locals and skiers). Wouldn't really combine it with anything else (except maybe Lassen or Brokeoff Mountain on the way north, or maybe visit to Castle Crags State Park).
P.S. For a good training/conditioning peak that is more local, you might check out Cone Peak, south of Big Sur, in the Ventana Wilderness. I think it is about 20 miles or so round trip (backpacking camp 5 miles if one likes), with 5000-plus feet of gain.
http://www.summitpost.org/cone-peak/150519. Can't beat the views up and down the coast...assuming you're not socked in!
P.S.S. If you have a choice between a day off at Cottonwood Lakes TH (i.e. Horeshoe Meadow), and at Cottonwood Lakes, I would hike in and take the day at Cottonwood Lakes. It is an easy hike into the Lakes...almost a day of rest itself. Then you can spend a day fishing or exploring the basins below the ridges (maybe hike over to Arc Lake, etc).
