The only table service restaurant that has a good view of illuminations is Rose and Crown. If your on the bottom level of the patio you have a great view. If your on the top level the higher fireworks are blocked from your view. Rose and Crown has a special area to watch the fireworks from and your view is unobstructed from there.
Les Chefs de France has a view of the fireworks, but it is through tall windows and there are bound to be many prople in front of you. They do dim the lights and you can hear the music from there.
No other table service restaurant that I can think of has a view of illuminations. I like Rose and Crown for the fireworks, but I also like Les Chefs for the atmosphere and food (Rose and Crown is a bit cheaper). If it's your first time seeing Illuminations I would go for Rose and Crown. If you've seen Illuminations before then I would go to Les Chefs.
The issue of a 20 month old is a little trickier. All restaurants at WDW are kid friendly to a point. My kids are 20 and 24 years old so it's not an issue with me. Last week I was at Rose and Crown and there was a large family with a young child that cried for 45 minutes. I felt that the family was negligent in not taking the young one out so that others could enjoy their meal. I know that when my children were young that's what my wife or I would do. Outside of that the Rose and Crown deck may be a better place for a child. Les Chefs is crowded and does not have much room for strollers, but on the other hand if your child is afraid of the loud noises from the fireworks then Les Chefs would be a better choice.
In the end it comes down to what's more important. The view then Rose and Crown, the atmosphere then Les Chefs.
