Yes, you can, but you would be best served by finding rpm packages that have been built specifically for SuSE. In fact, if you go to the SuSE site to get updates to applications on your system, those updates will be rpms.
Check out 'man rpm'. The simplest way is 'rpm -i the.package.to.install.rpm' or 'rpm -U the.package.to.upgrade.rpm'. You may get some warnings about dependencies if you don't have some of the other necessary packages installed. You might also want to use the -v option to see more information about the install/upgrade.