Major, yes, EIDE is newer than IDE. I don't think any drives are made that are just IDE anymore. So now, whenever anyone says IDE, they really mean EIDE.
gizmo, like the others are saying, stay away from SCSI drives. Stick with either a SATA or an EIDE drive. They're both reliable, and you're going to get more storage for your money.
I don't usually hear of SCSI drive being used, except in servers.