If the winter squash is mature enough, you can't make a dent in the skin with a finger nail. If it's not ripe enough, you can just wait a few weeks, and it should ripen even if it's not on the vine.
The length of time for baking depends on it's size. An Acorn squash which is small will bake at 350 degrees in about an hour. Larger squash will take a while longer. I just stab them with a knife so they don't explode in the oven, and put them in a pan and bake them with the seeds inside. They stay nice and moist then. When they are fully cooked, you can squeeze them and they are soft. If they are firm, then bake them longer. I then take them out of the oven and put them on a cutting board and cut them in half and scoop out the seeds. I put them back into the pan, cut side up, and put in a big chunk of butter about 2 Tablespoons, and about 1/4 cup of brown sugar and put them back into the oven until the brown sugar is melted into the butter. If I have a larger squash, I ususally scoop out the meat of the squash into a bowl and mash it with butter and brown sugar. Or, you can cut it into 4ths, and do the oven butter/brown sugar melting trick. Try it you'll like it.
Sometimes I have a butternut squash. Those I like to cut up raw into one inch cubes and put them into a covered casserole dish. I pour in a can of chunk pineapple with the juice, and bake it covered until it's tender.
Do you know what kind of squash you have Rick?