When first loading up I get the normal start screen with Ready to play Minecraft 1.8.1 in the bottom right hand corner, but then when I click the Play button I get a dialogue box pop up with the following text

---- Minecraft Crash Report ----
// Shall we play a game?

Time: 1/31/15 9:25 AM
Description: Initializing game

ctz: Unable to fit: minecraft:blocks/wool_colored_red - size: 128x128 - Maybe try a lowerresolution resourcepack?
at ctw.c(SourceFile:60)
at cua.b(SourceFile:197)
at cua.a(SourceFile:77)
at cxh.j(SourceFile:553)
at cxh.a(SourceFile:139)
at cxk.a(SourceFile:23)
at cvt.a(SourceFile:99)
at bss.ak(SourceFile:440)
at bss.a(SourceFile:302)
at net.minecraft.client.main.Main.main(SourceFile:124)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

– Head –
Stacktrace:
at ctw.c(SourceFile:60)
at cua.b(SourceFile:197)
at cua.a(SourceFile:77)
at cxh.j(SourceFile:553)
at cxh.a(SourceFile:139)
at cxk.a(SourceFile:23)
at cvt.a(SourceFile:99)
at bss.ak(SourceFile:440)

– Initialization –
Details:
Stacktrace:
at bss.a(SourceFile:302)
at net.minecraft.client.main.Main.main(SourceFile:124)

– System Details –
Details:
Minecraft Version: 1.8.1
Operating System: Mac OS X (x86_64) version 10.6.8
Java Version: 1.6.0_65, Apple Inc.
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
Memory: 160636968 bytes (153 MB) / 315400192 bytes (300 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 5 total; -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 1.8.1
LWJGL: 2.9.2
OpenGL: NVIDIA GeForce 9400 OpenGL Engine GL version 2.1 NVIDIA-1.6.36, NVIDIA Corporation
GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because ARB_framebuffer_object is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

Using VBOs: No
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: [KayneCraft4.2x128.zip]
Current Language: English (UK)
Profiler Position: N/A (disabled)