Restaraunts: Flying Fishbone (reserve early, it goes quickly), West Deck, Zeerovers, Madame Janettes are some of our favorites. You really cant go wrong, even the smaller local shops are phenomenal.
Beaches: Eagle is the best, but every beach has something to offer. If you prefer quiet and shallow water try Baby or Mangel Halto. Try them all if you have time though!
Activities: We love doing ATV/UTV excursions to the Natural Pool and Bridge, Caves, Gold Mine, etc. But if you rent a Jeep or another durable vehicle you can explore Arikok National Park on your own a bit and hit some of those locales. Most of the shopping is done in Oranjestad, its very touristy and much of it caters to the ships. Go see the lighthouse up north and take some time to explore the dunes, they are very cool.
Accomodations: We typically AirBnB but you cant really go wrong with any of the resorts, they are positioned on great beaches and very close together.
Weather is always perfect, if it rains, it does so for about 10-15 minutes and then POOF, gone. Water is warm and clear.
We love Aruba and have been there many times now. The East side of the Island has the most nature and history but the water is rough so dont plan on swimming there or at least wade out far. Very treachurous. The landscape is very rocky and reminiscent of Mars. The whole island is only 20 miles or so, so getting around is very easy and fairly quick.