Trawling through the recent threads, I had to stop at this and have my own say about my own guilty pleasures, most of them from listening to music while growing up.
Bear in mind that my tolerances of music are very different and varied compared to some others, as I feel a lot of so-called "guilty pleasure" songs (including several - possibly too many - already mentioned so far in the thread) are probably undeserving of their status and are genuinely great songs.
That said, I do have a number of choices that I feel particularly guilty about liking. A LOT. I could comment on the relative merits (or lack thereof) contained within these pieces of, er, music, but instead I'll simply let the music speak for itself - long story short, I love each and every one of them regardless.
This is by no means an exhaustive list:
"Doop" - Doop
http://www.youtube.com/watch?v=tvLDm8821jQ
"Them Girls Them Girls" - Zig & Zag
http://www.youtube.com/watch?v=eH80X3lC5M0
"C'est La Vie" - B*Witched
http://www.youtube.com/watch?v=UvjLgjtJKsc
"Disco Duck" - Rick Dees and his Cast of Idiots
http://www.youtube.com/watch?v=irgJPqkuakM
"Chacarron" - El Chombo
http://www.youtube.com/watch?v=pfElckgKbPE
"Saturday Night" - Whigfield
http://www.youtube.com/watch?v=TOvcytygY_M
"Hey Baby" - DJ Otzi
http://www.youtube.com/watch?v=aNsmiqmaEWo
"Blue (Da Ba Dee)" - Eiffel 65
http://www.youtube.com/watch?v=68ugkg9RePc
"Axel F" - Crazy Frog
http://www.youtube.com/watch?v=k85mRPqvMbE
"Floral Dance" - Terry Wogan
http://www.youtube.com/watch?v=ElnCI1fkfFM
I have this one on my mp3 player.
"I Touch Myself" - Rolf Harris
http://www.youtube.com/watch?v=U8Yxmz-csB4
Also, pretty much any selected piece by the James Last Orchestra or Lil Jon.
Finally, pick a mashup. Any mashup.

To be fair though, many mashups, if done well, are decent songs in their own right, but a lot of them fall squarely into guilty pleasures. For example:
Grease vs. Wise Guys
http://youtu.be/f_r4Ieh7Lz0
Michael Jackson vs. Nirvana
http://youtu.be/JNUTYHJrutw
Will Smith vs. Muse
http://youtu.be/z6H0q71f9XU
The now legendary "I Kissed A Barbie Girl"
http://youtu.be/oKF-P3Y3nm8
Beatles vs. Radiohead vs... just listen:
http://youtu.be/0UvKEuCQ_EY
And finally, my personal favourite guilty pleasure of them all: Rick Astley vs. Sir Mix-A-Lot
http://youtu.be/Z9387zmssuE
I mean, I could go on...
