It depends on where you will live in Roseville. A lot of Roseville was built out in the past 10 to 15 years. In many neighborhoods in Roseville, the local parishes are still raising money to buy land and construct a Church. Then later as they raise more money, then they will open up a school.
You should be able to find the location of the Catholic Schools here
Roman Catholic Diocese of Sacramento - Catholic Schools
and find more feed back on them here.
Great Schools - Public and Private School Ratings, Reviews and Parent Community
In general, the public schools in Roseville are fairly good, which means that is less demand for Catholic Schools in Roseville compared to Sacramento where the public schools aren't as strong.
In the Roseville area, there isn't a Catholic high school. If you are looking for that, you will need to take your kids into Sacramento itself. The Catholic High Schools in the region are as follows.
If you are planning on sending your kids to Catholic schools in any case, what might make sense is to live closer to those schools in Sacramento. Housing in general is less expensive in Sacramento in part because the public schools in Sacramento aren't as strong. If you won't be using them, you probably could manage to live some place cheaper that is closer to the Catholic schools your kids will be attending.
Jesuit High School, Sacramento - Home
St. Francis High School - Sacramento, CA
Loretto High School - Home Page
Christian Brothers High School - Home
Cristo Rey High School - Sacramento
About a month ago, they announced that Loretto will close at the end of this year, but there is some talk about trying to reverse that decision.
Christian Brothers is a co-ed Catholic High School. Loretto and Saint Francis are all female and Jesuit is all male.
At Cristo Rey, the students are supposed to work part time to help keep tuition down. I believe that school is co-ed as well but I am not entirely sure.