Having gome thorugh the various reviews on tripadvisor, we opted to stay at the Hotel Eur. We were not disappointed. It has everything you'd expect (and more) from a good three star hotel. It's not cheap though. The prices are similar to some four star hotels in the area.
With one child, we stayed in a triple room which was small. It's a regular double sized room with a narrow folddown bed that sits in front of the patio doors (which made exit to the patio a bit awkward). You don't spend a lot of time in the room so it's fine, particularly with a young child but it might be a bit cramped if the third person was an older child or adult.
The room itself is decorated to a very good standard with a large LCD screen tv with all basic SKY channels as standard. Very useful. The bathroom is a reasonable size with a good shower. The patio was very nice although there's own no privacy (only a low wall) from your immediate neighbours on either side. The air-conditoning works well and there's a small fridge into which you can put your personal stuff.
The breakfast is okay without being spectacular. There's no fresh fruit and the orange juice is served in plastic disposable cups. There's a small selection of cereals, pastries, cheese and salamies, etc. There's no hot option. While we just stayed on a B&B basis, we could see that those who opted to avail of full or half board were required to express their lunch and dinner preferences while eating breakfast. Don't think I'd fancy this but it seems to be fairly standard.
Outside, the garden area is beautiful and very well maintained with planty of shared seating areas to relax away from the glare of the sun. The pool is nice and never seems to be too busy. It looks a little old but is perfectly fine. There's a shallow pool that's perfect for toddlers. The slide into the pool was a bit hit with all children, including our own little guy. The place had a nice family atmosphere without being too overrun. There were always available sunbeds.
Internet access is available in the hotel lobby at a cost of €6 an hour. There's a small number of bikes for hire (some with child seat) for €2 an hour.
In terms of location, the Hotel Eur is perfect. It's only a few short steps from the promenade and it's many restaurants and a short stroll from the central pier.
Overall, I'd recommend the Hotel Eur for anyone staying in Lido.