I'm a 42 year old male, if that matters. how long before i can talk and eat normally with my new full set of dentures?

It all matters : Age, expectation, height, weight, ethnicity, emotional aptitude, education, native language, this is by no means an exhaustive list of factors affecting how you will function with denture. If you are asking when will you function like if you had your natural teeth.The real answer is never. Maximum gains are achieved at 8 weeks. The worlds greatest denture functions at 15-20 % of natural teeth.

New dentures: Function and retention depends on many factors: amount of bone and size of your bony ridge, the shape of the palate, amount and type of saliva, and facial musculature to name a few. You probably will never be able to eat like with your teeth, but it will improve over time. Practice reading out loud to help with talking. Ask your dentist for suggestions.