Because I have been asked so many times about them, I forced myself to read some of them.
The answer in a nutshell?
Yes, they are anti-Catholic and viciously so. For that matter, they are anti-Orthodox, and anti-Anglican, and anti-Lutheran, etc. They are anti anything except a very narrow form of American Fundamentalism. The writing is also incredibly atrocious.
The two authors, Tim LaHaye and Jerry B. Jenkins, are very definitely fundamentalists. LaHaye, who provides the “theology” behind the books, is a product of Bob Jones University. I’ve read some of his stuff and seen him on TV. He comes off as incredibly arrogant and one gets the distinct impression that he is actually looking forward to seeing all his enemies roast in hell. Jerry B. Jenkins, who provides the actual novelization, should know better, and apparently, used to know better – writing for influentual, conservative – but not inflammatory – evangelical Protestant publications.