You have to put an f after 0.25 to make it float instead of double. Unity works with floats, get used to put an f after every decimal number you use to make sure it is a float.
You have also miswrotten GetComponent as the C of component must be upper case. In Input.GetAxis() you must pass an string as you do in animator.SetFloat().
using UnityEngine;
using System.Collections;
public class IdleWalk : MonoBehaviour
{
Animator animator; public float DirectionDampTime = 0.25f;
void Start()
{
animator = GetComponent<Animator>();
}
void Update()
{
float h = Input.GetAxis("Horiszontal");
float v = Input.GetAxis("Vertical");
animator.SetFloat("Speed", h * h + v * v);
animator.SetFloat("Direction", h, DirectionDampTime, Time.deltaTime);
}
}