A Collection Object Will Store Disk Objects

I would use two classes:
Disk
Collection

Disk objects will contain the id, type (CD/DVD), title, a track listing, the artist's name, genre, length and status(rented, bad)

A Collection object will store Disk objects.

For Disk, there need to be operations to set, change, and get each of those fields.
For Collection, there needs to be an operation to add, search, remove Disk

Class diagrams:

Disk
Id : String
Type : String
Title : String
Tracks : String
Artist : String
Genre : String
Length : Double
Status:String
setId(Id:String):void
getId():String
setType(Type:String):void
getType():String
setTitle(Title:String):void
getTitle ():String
setTracks(Tracks:String):void
getTracks ():String
setArtist (Artist:String):void
getArtist():String
setGenre (Genre:String):void
getGenre ():String
setLength (Length:Double):void
getLength():Double
setStatus(Status:String):void
getStatus():String

Pseudocode: (of course it's always good to rewrite this in your own words.)

For the Disk class:

Class CD

Id as String

Type as String
Title as String
Tracks as String
Artist as String
Genre as String

Length as Double

Subprogram SetId(NewId)
Set Id = NewId
End Subprogram

Subprogram SetType(NewType)
Set Id = NewType
End Subprogram
Subprogram SetTitle(NewTitle)
Set Title = NewTitle
End Subprogram
Subprogram SetTracks(NewTracks)
Set Tracks = NewTracks
End Subprogram
Subprogram SetArtist(NewArtist)
Set Artist = NewArtist
End Subprogram
Subprogram SetGenre(NewGenre)
Set Genre = NewGenre
End Subprogram

Subprogram SetLength(NewLength)
Set Genre = NewLength
End Subprogram

Function GetId() As String
Set GetId = Id
End Function
Function GetType() As String
Set GetType = Type
End Function
Function GetTitle() As String
Set GetTitle = Title
End Function
Function GetTracks() As String
Set GetTracks = Tracks
End Function
Function GetArtist() As String
Set GetArtist = Artist
End Function
Function GetGenre() As String
Set GetGenre = Genre
End Function

Function GetLength() As Double
Set GetLenght = Lenght
End Function
End Class

For the Collection class:

Class Collection
D as Disk[100]
Subprogram AddDisk(NewDisk)
C.add(NewDisk)
End Subprogram
Subprogram RemoveDisk(BadDisk)
C.remove(BadDisk)
End Subprogram
Function SearchDisk(n) As Real
Set searchDisk = D[n]
End Function
End Class

GUI