There are 40 Pokémon with 500 or more Base Stat in the Unova Pokedex. That means there are 116 Pokémon with less than 500, so I will just list the over 500 ones. EDIT I have now added all of the Unova Dex
From best to worse:
White Kyurem 700
Black Kyurem 700
Reshiram 680
Zekrom 680
Kyurem Normal form 660
Victini 600
Hydreigon 600
Landorus Incarnate 600
Landorus-Therian 600
Meloetta Aria form 600
Meloetta Pirouette form 600
Genesect 600
Cobalion 580
Terrakion 580
Virizion 580
Tornadus-Incarnate form 580
Tornadus-Therian form 580
Thundurus-Incarnate form 580
Thundurus-Therian form 580
Keldeo 580
Keldeo Resolute 580
Archeops 567
Volcarona 550
Darmanitan Zen Mode 540
Haxorus 540
Vanilluxe 535
Serperior 528
Emboar 528
Samurott 528
Klinklang 520
Chandelure 520
Eelektross 515
Zoroark 510
Mienshao 510
Braviary 510
Mandibuzz 510
Krookodile 509
Excadrill 508
Gigalith 505
Conkeldurr 505
Source: http://pokemondb.net/pokedex/black-white-stats
EDIT: Here is the list of below 500 Pokémon.
Seismitoad 499
Simisage 498
Simisear 498
Simipour 498
Zebstrika 497
Carracosta 495
Escavalier 495
Accelgor 495
Stoutland 490
Leavanny 490
Sigilyph 490
Gothitelle 490
Reuniclus 490
Bisharp 490
Bouffalant 490
Ferrothorn 489
Scrafty 488
Musharna 487
Beheeyem 485
Beartic 485
Cryogonal 485
Druddigon 485
Heatmor 484
Durant 484
Cofagrigus 483
Golurk 483
Whimsicott 480
Lilligant 480
Darmanitan Standard Mode 480
Jellicent 480
Unfezant 478
Scolipede 475
Crustle 475
Sawsbuck 475
Garbodor 475
Swanna 473
Galvantula 472
Stunfisk 471
Cinccino 470
Alomomola 470
Throh 465
Sawk 465
Amoonguss 464
Maractus 461
Basculin 460
Liepard 446
Audino 445
Klang 440
Emolga 428
Swoobat 425
Watchog 420
Zweilous 420
Pignite 418
Servine 413
Dewott 413
Fraxure 410
Gurdurr 405
Eelektrik 405
Archen 401
Vanillish 395
Boldore 390
Gothorita 390
Palpitoad 384
Swadloon 380
Herdier 370
Duosion 370
Lampent 370
Vullaby 370
Whirlipede 360
Larvesta 360
Tranquill 358
Tirtouga 355
Krokorok 351
Mienfoo 350
Rufflet 350
Scraggy 348
Pawniard 340
Deerling 335
Frillish 335
Elgyem 335
Zorua 330
Trubbish 329
Drilbur 328
Dwebble 325
Axew 320
Joltik 319
Pansage 316
Pansear 316
Panpour 316
Darumaka 315
Karrablast 315
Woobat 313
Sewaddle 310
Snivy 308
Tepig 308
Oshawott 308
Timburr 305
Ducklett 305
Vanillite 305
Ferroseed 305
Cubchoo 305
Shelmet 305
Yamask 303
Golett 303
Minccino 300
Klink 300
Deino 300
Blitzle 295
Tympole 294
Foongus 294
Munna 292
Sandile 292
Gothita 290
Solosis 290
Purrloin 281
Roggenrola 280
Cottonee 280
Petilil 280
Lillipup 275
Tynamo 275
Litwick 275
Pidove 264
Venipede 260
Patrat 255
