Get the default user profile

Default_User_Profile_Apex

//find all Opportunity record types
			List<Schema.RecordTypeInfo> infos = Schema.SObjectType.Event.RecordTypeInfos;
			Id defaultRecordTypeId;

			//check each one
			for (Schema.RecordTypeInfo info : infos) {
			  if (info.DefaultRecordTypeMapping) {
			    defaultRecordTypeId = info.RecordTypeId;
			  }
			}
			recordTypeId = defaultRecordTypeId;
			//here is the default Opportunity RecordType Id for the current user
			System.debug(defaultRecordTypeId);