A list from Jane Mallison's 2007 work. One topic per month with 10 classics per topic (indexed below), giving The Book Smart 120. Also 150+ recommended reads.
Towering Works to Read in Translation (1-27)
1 4-7 12 17-18 22 27
Some Notable Biographies (28-54)
28 32 37 38 41 44 46 50-52
Young Men on a Quest (55-68)
55 57-61 64 66-68
Strong Women, Admirably So and Otherwise (69-90)
69 70 75-80 82-84
Crimes of Various Sorts (91-109)
91-93 96 100 101 105-107 109
Books with Varied Venues (110-131)
110 111 113-115 120 123 125 128 131
Unaccustomed Places, Real and Fancied (132-153)
132 135 138 140 143 144 147-150
Smiles at the Human Condition (154-176)
154 159 162 163 165-168 171 176
Some Great 18th Century Works (177-202)
177 183-185 188-191 194 200
The Pains and the Pleasures (206-227)
203 206 207 211 212 215 216 220 224 225
On the Battlefield and Back Home (228-247)
228 232-234 236 237 239 243 244 247
Winners of Major Awards (248-273)
248 251 255 257 260 264 265 268 271 272