It always amazes me that every famous person's first album was a seminal and cool long player. Surely someone must have started off with something naff? On this theme it seems most people are being honest on this thread
Very similar to this my first album was more than likely one of The Top Of The Pops compilations which features songs by cover bands and, I may be wrong here, but shortened versions too. The covers to these were in respect the best bit about them.
Twist 'n Shout EP by the Beatles, still have it somewhere.