IMO, if you're going to compare orcs and giants, you should probably use the same types. The orc berserker and Hill giant are both basic brutes:
[sblock]Orc Berserker Level 4 Brute
Medium natural humanoid XP 175
Initiative +3 Senses Perception +2; low-light vision
HP 66; Bloodied 33; see also warrior’s surge
AC 15; Fortitude 17, Refl ex 13, Will 12
Speed 6 (8 while charging)
m Greataxe (standard; at-will) ✦ Weapon
+8 vs. AC; 1d12 + 5 damage (crit 1d12 + 17).
M Warrior’s Surge (standard, usable only while bloodied; encounter)
✦ Healing, Weapon
The orc berserker makes a melee basic attack and regains 16 hit
points.
Alignment Chaotic evil Languages Common, Giant
Skills Endurance +10, Intimidate +6
Str 20 (+7) Dex 13 (+3) Wis 10 (+2)
Con 16 (+5) Int 8 (+1) Cha 9 (+1)
Equipment leather armor, greataxe
Hill Giant
Level 13 Brute
Large natural humanoid (giant)
XP 800
Initiative +5 Senses Perception +7
HP 159; Bloodied 79
AC 25; Fortitude 27, Reflex 21, Will 23
Speed 8
Greatclub (standard; at-will) WeaponReach 2; +15 vs. AC; 1d10 + 5 damage.
Sweeping Club (standard; encounter) Weapon
The hill giant makes a greatclub attack against two Medium or smaller targets; on a hit, the target is pushed 2 squares and knocked prone.
Hurl Rock (standard; at-will) Ranged 8/16; +15 vs. AC; 2d6 + 5 damage.
Alignment Chaotic evil
Languages Giant
Skills Athletics +16
Str 21 (+11) Dex 8 (+5) Wis 12 (+7) Con 19 (+10) Int 7 (+4) Cha 9 (+5)
Equipment hide armor, greatclub[/sblock]
And the Orc Bloodrager to the Earth Titan (both elite brutes):
[sblock]Orc Bloodrager Level 7 Elite Brute
Medium natural humanoid XP 600
Initiative +5 Senses Perception +3; low-light vision
HP 194; Bloodied 97; see also warrior’s surge
AC 21; Fortitude 22, Refl ex 19, Will 17
Saving Throws +2
Speed 6 (8 while charging)
Action Points 1
m Greataxe (standard; at-will) ✦ Weapon
+11 vs. AC; 1d12 + 5 damage (crit 1d12 + 17); see also blood for
blood.
M Warrior’s Surge (standard, usable only while bloodied; encounter)
✦ Healing, Weapon
The orc bloodrager makes a melee basic attack and regains 48
hit points.
MWounded Retaliation (immediate reaction, when hit by an
adjacent enemy; at-will)
The orc bloodrager makes a melee basic attack against the
enemy.
Blood for Blood ✦ Healing, Weapon
When it hits a bloodied enemy, the orc bloodrager deals an extra
5 damage and regains 10 hit points.
Alignment Chaotic evil Languages Common, Giant
Skills Endurance +11, Intimidate +8
Str 20 (+8) Dex 15 (+5) Wis 11 (+3)
Con 17 (+6) Int 9 (+2) Cha 10 (+3)
Equipment leather armor, greataxe
Earth Titan
Level 16 Elite Brute
Huge elemental humanoid (earth, giant)
XP 2,800
Initiative +7
Senses Perception +9
HP 384; Bloodied 192
AC 31; Fortitude 33, Reflex 27, Will 28
Immune petrification
Saving Throws +2
Speed 6
Action Points 1
Slam (standard; at-will)Reach 3; +20 vs. AC; 2d10 + 6 damage.
Double Attack (standard; at-will)The earth titan makes two slam attacks.
Hurl Rock (standard; at-will) Ranged 20; +18 vs. Reflex; 2d8 + 6 damage, and the target is dazed (save ends).
Earth Shock (standard; encounter) Close burst 2; +18 vs. Fortitude; 2d10 + 6 damage, and the target is stunned until the end of the earth titan’s next turn. Miss: Half damage, and the target is not stunned.
Alignment Chaotic evil
Languages Giant, Primordial
Skills Athletics +19
Str 23 (+14) Dex 8 (+7) Wis 12 (+9) Con 22 (+14) Int 11 (+8) Cha 13 (+9)[/sblock]
The Hill Giant does indeed do less damage than the Berserker, but I expect that this is because he is one handing a (human) greatclub whereas the orc is two-handing a greataxe. If you replaced his greatclub with a larger weapon I imagine the discrepancy would be fixed (although I am curious as to the reasoning behind it, assuming it wasn't just an oversight). My best guess would be that the hill giant, unlike the berserker, has a ranged attack as well.
The Titan does do significantly more damage than the Bloodrager though.