Well, you will only have 2 levels to play with at 10th level, since the Dracotaur costs 8 (3HD + 5LA). So you are looking for a Dracotaur Fighter 2 at this point.
With such low HD (only 5 at level 10) I would focus on maxing out Con so that you have some staying power, and then Str to make up for lost BAB in some way. With 40 point buy I'd place it something like this...
Str: 16 (+3)
Dex: 12 (+1)
Con: 18 (+4)
Int: 8 (-1)
Wis: 12 (+1)
Chr: 14 (+2)
Then add in the Dracotaur racial mods...
Str: 24 (+7)
Dex: 14 (+2)
Con: 24 (+7)
Int: 10 -
Wis: 12 (+1)
Chr: 16 (+3)
So a Dracotaur with those stats would look something like this.
Hit Points: 46 (3d12+21)
AC: 18 (10[base]-1[Size]+2[Dex]+5[Natural]+2[Armor])
Initiative: +2
Speed: 50ft
Saves:
Fort: +10 (3[base]+7[Con])
Refx: +5 (3[base]+2[Dex])
Will: +6 (3[base]+1[Wis]+2[Iron Will])
BAB/Grapple: +3/+14
Attack: +9 Spear
Damage: 2d6+10 (20x2) Spear
Feats: Armor Proficiency (light), Iron Will
Skills: Balance +5, Intimidate +7, Jump +16, Knowledge (arcana) +4, Listen +6, Sense Motive +6, Spellcraft +4, Spot +6, Survival +6, Swim +8, Use Magic Device +7
Special Attacks: Spit fire
Special Qualities: Darkvision 60 ft., immunity to magic sleep effects and paralysis, low-light vision
Notice the still low HP and saves. Your HP should ramp up quickly with such a high Con though. And now a Dracotaur Fighter 2. Dont forget you can rearrange the Feats/Skills how you like when you are making a monster PC. So I'll use my recomendations

Also, I'm not sure if you can take Leadership until your HD is 6, or if it is based on level etc. I'll assume you can though.
Hit Points: 71 (3d12[Racial]+2d10[Fighter]+35[Con])
AC: 18 (10[base]-1[Size]+2[Dex]+5[Natural]+2[Armor])
Initiative: +2
Speed: 50ft
Saves:
Fort: +13 (6[base]+7[Con])
Refx: +5 (3[base]+2[Dex])
Will: +4 (3[base]+1[Wis])
BAB/Grapple: +5/+16
Attack: +12 MW Spear
+7 MW Rock
Damage: 2d6+11 (20x2) MW Spear
2d6+10 (20x2) MW Rock
Feats: Weapon Focus: Spear, Point Blank Shot, Precise Shot, Leadership
Skills:
Special Attacks: Spit fire
Special Qualities: Darkvision 60 ft., immunity to magic sleep effects and paralysis, low-light vision
Your low Will save wont be much of an issue since being a dragon makes you immune to many of the perils of having such a low Will Save. Assuming you are using normal levels for gold, I'd reccomend the following equipment. 49,000g
+1 Spear: 2,300g
+1 Throwing Rock: 2,300g
+1 Large non-humanoid Breastplate: 1,800g
Bracers of Con +2: 4,000g
Gloves of Dex +2: 4,000g
Belt of Giant Str +4: 16,000g
Cloak of Resistance +3: 9,000g
Ring of Protection +1: 2,000g
Amulet of Natural Armor +1: 2,000g
That leaves you about 6000g+ in change for potions or what not and your new character looks like this.
Str: 28 (+9)
Dex: 16 (+3)
Con: 26 (+8)
Int: 10 -
Wis: 12 (+1)
Chr: 16 (+3)
Hit Points: 76 (3d12[Racial]+2d10[Fighter]+40[Con])
AC: 25 (10[base]-1[Size]+3[Dex]+6[Natural]+6[Armor]+1[Deflection])
Initiative: +3
Speed: 50ft
Saves:
Fort: +17 (6[base]+8[Con]+3[Resistance])
Refx: +9 (3[base]+3[Dex]+3[Resistance])
Will: +7 (3[base]+1[Wis]+3[Resistance])
BAB/Grapple: +5/+18
Attack: +14 +1 Spear
+8 +1 Rock
Damage: 2d6+14 (20x2) MW Spear
2d6+14 (20x2) MW Rock
It's not bad... but you are going to be lagging behind any other dedicated melee character, or even an Ogre Hulking Hurler. The next couple of levels will make it better because you Con is so high, and you get a second attack at your next level.