There's no need for a task.
PHP Code:
#include <amxmodx>
#include <hamsandwich>
public plugin_init()
{
register_plugin("Menu on Spawn", "1.0", "OciXCrom")
RegisterHam(Ham_Spawn, "player", "OnPlayerSpawn", 1)
}
public OnPlayerSpawn(id)
{
if(is_user_alive(id))
client_cmd(id, "say /menu_command")
}