I have a list of them old and recent:-

Any Old Iron.
My Old Man.
Time to get Ready for Love (what chauvenistic crap).
Roses are Red my love, Violets are Blue (infact any drippy ballad.)
10/4 Rubber Ducky (England's answer to Convoy).
D I V O R C E.
Old Shep.
He's My Japanese Boy.
Baby Sitting Boogie.
Shut Up a Ya Face.
Ernie.
The Smurf Song.
I'm Going Overboard with a Capital O.
Anything by Sonia.
Chirpy Chirpy Cheep Cheep.
Anything that Tony Blackburn reckoned to be great.
But do you love me Daddy (Jim Reeves) retch!!
Any song where pop lyrics have been put to classical music
Motor Biking (singer was a part time Womble).
Chop Chop Chop(Sweet).
They swam and they swam right over the Dam.
Welcome Home.
Your the One that I Want (Hilda Baker's version).
Altogether in a Floral Dance (Terry Wogan).
Captain Beaky and his Band (Keith Michell).
I'm a Tiger (Lulu).
Billy Don't Be a Hero.
I've been to Paradise but I've never been to me (had two crying infants then and I just wanted to grab singer by the throat).
Motown doing Christmas songs (including Michael Jackson just on this occasion).
The dopey song from Pete's Dragon, I love you too.
Gypsies Tramps and Thieves (Cher).
Patches I'm Depending on you Son (depressing or what?).
Bridgit the Midget and the equally bad They call him the Streak both by Ray Stevens.
Any manufactured pink clubby pop pap.
Jive Bunny.

Time to Get Ready for Love is the ultimate worst song I have ever heard.