It is important to choose which journal you publish in carefully to maximize dissemination, visibility and citations to your research.
To find journals in a new subject area or seek alternatives to known journals, search a database such as Scopus or Web of Science for articles on your topic, and filter the results by journal title. (Access databases via OxLIP+)
Some suggested sources for checking a journal's credentials:
Beall's list of possible predatory publishers shut down in January 2017, as reported for example in Inside Higher Ed.
What's the difference? The JCR and SJR cover different but overlapping sets of journals and use different algorithms to calculate impact. See the Bibliometrics LibGuide for full details.