Snakes in house
Thank you for your question. The snakes in the photos are juvenile rat snakes (Pantherophis obsoleta lindheimeri). They are non-venomous. Juveniles are often found in and around structures. Rat snakes kill their prey by constriction. They are excellent climbers. They feed primarily on rodents, but will also eat young squirrels and birds. They will also visit chicken coops and swallow eggs and will feed on young chicks.
Patterns of juveniles are somewhat different than adults. Adults are usually darker than the juveniles and the pattern is not always as sharp and distinct. They can reach lengths in excess of 72 inches.
For more information on this species, visit this link at the University of Texas at Arlington:
I wouldn't count on guinea fowl keeping snakes away. Flocks of them have been known to attack snakes (visit this link at eXtension: http://articles.extension.org/pages/67816/raising-guinea-fowl), but I don't believe you can depend on them to consistently do that. The best thing you can do to reduce the chance of encountering snakes is practice good housekeeping around your yard. That involves keeping your grass cut to a reasonable height and not allowing piles of material, for example, lumber, bricks, dead limbs or leaves, to accumulate in the yard. Anything that provides good habitat for rodents will increase your chances of encountering snakes.
Hope this answers your question, and thanks for using Ask an Expert.