I'm going to do this in a question and answer format, mainly because it's easier for me -_-
1. I can execute "runInstaller" as root (although, it halts saying that I can't run this as root), but when I run it as oracle I get an error "./runInstaller: line 83: 3808 Segmentation fault $CMDDIR/install/runInstaller ${NONRAC_OPTION} $*".
Add the oracle user to the root group, and it should work.
2. When trying to log into iSQLPlus (SQLPlus web interface), I get an error "ERROR - ORA-12162: TNS:net service name is incorrectly specified".
When you start iSQLPlus, the ORACLE_HOME and ORACLE_SID environment variables weren't set properly.
isqlplusctl stop ORACLE_HOME=/u01/app/oracle/product/10.1.0/db_1 ORACLE_SID=test export ORACLE_HOME ORACLE_SID isqlplusctl start