This book contains two of Lovecraft's three novels. (The third and far better of the three is The Case of Charles Dexter Ward.) Lovecraft is at his best in novelette form, but At the Mountains of Madness is a worthwhile novel. The same cannot be said for The Dream-Quest of Unknown Kadath, which displays all the worst Lovecraftian traits: florid prose, absence of characterization, no dialog.

• At the Mountains of Madness: An Antarctic expedition uncovers an ancient city and their long-extinct inhabitants. A solid short novel, well worth reading.
• The Dream-Quest of Unknown Kadath: Randolph Carter enters dreamland in search of the city of Kadath. Not worth reading.

The short stories in this book outshine the two short novels. Through the Gates of the Silver Key is among the best.

• The Dreams in the Witch-House
• The Statement of Randolph Carter
• The Silver Key
• Through the Gates of the Silver Key

However, this book is not the best introduction to H.P. Lovecraft. Find a volume that contains The Shadow Over Innsmouth, The Dunwich Horror, The Colour Out of Space, and The Call of Cthulhu. Those are the best introduction to Lovecraft.