There are a few main variables that will result in soggy, swollen pasta leftovers. For example, the sauce you serve the pasta with could be leaching out liquid which is being absorbed by the pasta. This is especially likely if you often find water pooling underneath your Spag Bol. This can be avoided by cooking the sauce for longer so that the excess water evaporates. As you said though, standing for long periods is difficult for you. So rather than standing in front of the cooker for a few hours, stirring the sauce and making sure it doesn't catch. You could bake the sauce in the oven, on a low to medium gas mark / temperature. The other really great thing you can do is to use a small amount of Xanthan gum to stop the water from leaching out.
Xanthan gum is the product of fermenting certain simple sugars. The resulting ferment is then dried to a powder. The powder is then used as an thickener and emulsifier. It's commonly used in salad dressing to prevent them splitting, as well as all manner of other commercially prepared foods and deserts (it's what makes store bought milk shakes feel thick and rich, despite often only being made with skimmed milk). Another common use for Xanthan gum is as a thickening agent for water, for people who have difficulty swallowing. The difficult think about Xanthan gum though, is that it's difficult to mix into water without it clumping into little "pearls". But when you're cooking something like a pasta sauce, it's extremely easy to just mix it, in a small bowl, with a small amount of oil, and then stir the mixture into the sauce.
I usually cook enough Spag Bol for four greedy adults, plus two portions for the freezer, and it only takes about a quarter of a teaspoon of powder to stop the sauce releasing water. Making sure the sauce doesn't release excess moisture should help to prevent it the pasta beoming soggy, if the pasta is stored with the sauce mixed through it, on it, or off to the side.
You could also be overcooking the spaghetti. Fortunately spaghetti is perhaps the easiest pasta variety to cook "correctly". If you fish a single spaghetto out of the water and pinch it in half between your thumbnail and finger, you can see how cooked it is. If you see a pale, white dot in the centre of the spaghetto, then that means it is uncooked. If there is no dot, then the spaghetti is either perfectly cooked or overcooked. You use the size of this dot as it shrinks as a guide, in order to estimate how much more cooking it needs. You can time it so that you drain the spaghetti just as the dot has almost disappeared. You can the put the spaghetti back in the pot, stir in a knob of butter and cover it for another minute. It's a method I learned from an episode of The Sopranos of all things but it really works!
Some chefs cook their spaghetti so that the core is still slightly undercooked but despite what anyone might tell you, you can cook your spaghetti how ever you like!
The other thing that might be happening, if you don't have the same issue with soggy spaghetti as your son does, is that you son might be reheating it in such a way that the sauce has time to simmer or even boil the spaghetti. If you reheat spaghetti in a lot of sauce, it can go soggy. Where as if the spaghetti is un-sauced, it can dry out. Epically in the microwave.
As for the question of turkey mince recipes...
Turkey mince makes a lovely Chili Con Carne or taco filling. But if you're sensitive to the spiciness, then there's always Cottage Pie (which is really nice and potentially cheaper with a drained tin of green lentils added to the mince). Turkey burgers can be delicious if you season them well (have a look at J Kenji Lopez-Alt's recipe). You could make meatballs to go in a simple marinara sauce. You could make shish kebabs. There are also some really nice curries that use mince, that are fragrantly spicy but not necessarily hot spicy. There's also some Chinese recipes, such as Yuk Sung... if the raw lettuce is an issue for you, how about a Chinese flavoured mince based sauce, served with noodles... sort of a Chinese bolognese?
As one of the commenters said below your question. You have kind of asked several questions, which isn't typically allowed on Seasoned Advice. So rather than fall any further foul of the rules, I'll just say that if you'd like any further advice, especially in regards to recipe recommendations which are against the rules, I'd suggest you try the chat function on the left hand side of the page.
Best of luck!
