Hey, I'm studying CS at Yale. If you search through the forum you'll find a few threads with good opinion on Yale CS. The program is very strong, but it's not very big - we have about 25-30 majors in any given year. We are also more theoretical than most schools in the sense that there is not "Intro to Web Development" or anything like that at Yale. The core CS sequence is very good and most of the CS majors I know are pretty satisfied.
Tech internships are pretty easy to find because there's a massive demand right now. CS223 provides pretty much all the knowledge you need to do well in programming interviews. As for "business companies," not sure what you mean - every company is a business. If you're talking finance, then Yale is definitely a big target.
You should also email the director of undergraduate studies (DUS) of Comp Sci, who is
stanley.eisenstat@yale.edu. I don't know if you're an admitted student or not, but I'm sure he'd be up to answering any questions you have or redirecting you to the appropriate person. He can tell you more about the CS + Psych program among other things.