You can't just say "which do you want?". Each one has their perks, and has their downfalls.
1ST CHOICE: MIJUMARU (OSHAWOTT)
Mijumaru is not the favorite, but personally, I like it. Not for the base form though. When I choose a starter, I look at it's final evo. Mijumaru's has downfalls and perks, whereas the other two have 1 perk, and lots of downfalls. My Daikenki Will know Hydro Pump, Ice Beam, Hydro Cannon and Slash. a good combination of moves for the non-competitive trainer.
2ND CHOICE: TSUTAAJA (SNIVY)
Tsutaaja will be good if you like the grass type. The downfall is well, it's a grass type. The disadvantages are endless. Weaknesses. Lots of them. I could go more in depth with this, but I'm too lazy to.
3RD CHOICE: POKABU (TEPIG)
Pokabu. There is nothin good to say about Pokabu. Lowest base stat of any starter Pokemon. Ever. But, its final evo has the highest stats of any starter final evo ever. But just what we need. Another Fighting/Fire Final evo. >.< That is all I have to say.