I spent five nights with my 4 year old son at the Solplay hotel. The staff was very friendly and helpful, especially patient and kind with my boy. The hotel is located on a residential area to the west of Lisbon, out of the tourist buzz. It is within walking distance to small neighborhood shops, bakeries and a Lidl supermarket, and about 20 minutes walk to Algés station. The hotel provides free bus/shuttle on weekends to and from Marquis do Pombal square, next to the hop-on/hop-off tourist buses and the underground. The drivers were super friendly and accommodating, punctual and polite. On weekdays we walked to Algés, or booked a car service from the hotel desk, and took a bus or a taxi back to the hotel.
The hotel is a neat and clean (bit dated) building, with very large rooms (more like apartments), with fully furnished kitchenette (wasting-drying machine, oven, fridge with huge freezer, microwave, water cooker, toaster, etc) but has limited cooking utensils. Our room on the fifth floor faced the west, with an amazing terrace (huge) with sunset views to the hills, the river and the adjacent park. The beds could use some upgrading, but they were comfortable enough. Very quiet and dark at night, which was great for sleeping. The room was extremely clean and linens and towels were changed every day.
The indoor pool is decent in size and maintenance, with a hot tub. The hotel has other amenities which we didn't use. Good breakfast with fresh orange juice and nespresso coffee.