Wow! I can't believe that no one has really bothered to respond to your original question. So since I've been to DL at least 100 times over the last 32 years and actually wooed my wife while we were dating with some romantic DL trips, here's my advice for what it's worth.
Best romantic restaurant in park hands down is the Blue Bayou. It's really cool dining, sits right in the beginning of the Pirates of the Caribbean in a faux night atmousphere as the ride boats float by. A little pricey. And, unless they've somehow added a restaurant reservation phone line in the last few months, you will need to slog over to the restaurant to get reservations, doing it early in the AM for either a lunch or dinner rez. Reservations are usually filled for the day by about 11:00am.
There's also "Club 33" which is a hidden exclusive restaurant where you need to know someone in corporate power in order to gain access and get a table. I have never been, but my parents and several friends of mine have dined there and enjoyed it quite a bit. But again, you need to know someone "in power" who can get you in.
Best value and overall eats also resides in New Orleans Square. The French Market buffeteria for some reason is far superior to almost all other food services in DL. Plus they usually have a Dixieland jazz combo peforming. We eat here almost every visit.
I haven't been to Downtown Disney yet, but I know there are a few decent and semi-romantic places there. And stuff keeps changing at DCA, so I'm not sure what's even there anymore. Food was good when we went--we're partial to Bodein Bakery. There are also some fancier places to dine in the hotels, but again, it's been a long while since I've been to a Disneyland hotel.
Ride-wise, hit all the mountains, including Matterhorn. Definately go on Indiana Jones--it's the absolute best Disney ride ever. Roger Rabbit Cartoon Spin is fun. There are also some nice smaller unique to DL attractions in Fantasyland like Alice in Wonderland, Storybook Canal Boats (ride at night--much more romantic), Pinocchio, Mr. Toad's Wild Ride. And their car ride--Autopia--was just redone and is kind of cool--you do some "off-roading" and it's chalk full of very bad pun humor. The train around the park is kind of cool because there's a huge diorama of the Grand Canyon followed by dinosaurs.
And if you've never been on Star Tours, definately ride--it's really wonderfully cool if you haven't been exposed to the same old routine again and again and again...
If they are offering Fantasmic, definately take in a showing. Likewise at DCA, check out the Electrical Parade. I've also heard that the Blast Show is really great--although I have yet to see it.
Ride-wise at DCA, Soaring Over California, Grizzly River Run, California Screaming, and the Sun Wheel (giant ferris wheel) are cool rides. I'm also partial to Muppets 3-D. Romance can also be had by just taking in this park slower than you would it's next door neighbor by just exploring and soaking it all up. It's got some nice detail and scenery.
What to avoid? Hmm. That's a toughie. I'm not into Innoventions. Tiki Room can get on your nerves but makes a nice relaxing 15 minute break in the middle of a hot day. Tom Sawyer's Island is no fun if it's overrun with kids. And depending on your likes and dislikes, DCA is a bit heavy on carnival-type rides, although they are somewhat themed Disney-wise.
Use Fastpass whenever you can. We usually hit an area like Tomorrowland and will get a Fastpass for something like Space Mountain, then kill the time by doing Honey, I Shrunk the Audience or Astro Orbiter. Then just when our Fastpass return time is up, we'll dash off to get our next Fastpass, which in this case would be for Autopia or Star Tours. Then we'd kill the "return time" wait by finally riding Space Mountain then taking in some other nearby attraction--Train, Monorail, even Alice In Wonderland or the Teacups--until the Fastpass time begins for Autopia. From there we move from land to land, grabbing Fastpasses for the next attraction as we go. You avoid a lot of long lines this way. In fact, I think we killed an estimated 3 hours of line time by using 7 Fastpasses the last time we went to DL. Try it. It works, saves both your legs and sanity.
Hope this helps. Have a great honeymoon.
