when starting the game it takes a lot of time to the "Mojang" screen to load and then after a lot more of time the game crashes and this thing comes out:
---- Minecraft Crash Report ----
// Who set us up the TNT?

Time: 19:20 25/08/14
Description: Initializing game

ctx: Unable to fit: minecraft:items/leather_chestplate_overlay - size: 256x256 - Maybe try a lowerresolution resourcepack?
at ctu.c(SourceFile:60)
at cty.b(SourceFile:197)
at cty.a(SourceFile:77)
at cxf.j(SourceFile:553)
at cxf.a(SourceFile:139)
at cxi.a(SourceFile:23)
at cvr.a(SourceFile:99)
at bss.aj(SourceFile:437)
at bss.a(SourceFile:299)
at net.minecraft.client.main.Main.main(SourceFile:120)

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

– Head –
Stacktrace:
at ctu.c(SourceFile:60)
at cty.b(SourceFile:197)
at cty.a(SourceFile:77)
at cxf.j(SourceFile:553)
at cxf.a(SourceFile:139)
at cxi.a(SourceFile:23)
at cvr.a(SourceFile:99)
at bss.aj(SourceFile:437)

– Initialization –
Details:
Stacktrace:
at bss.a(SourceFile:299)
at net.minecraft.client.main.Main.main(SourceFile:120)

– System Details –
Details:
Minecraft Version: 1.8-pre2
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.7.0_65, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 165340880 bytes (157 MB) / 642252800 bytes (612 MB) up to 954728448 bytes (910 MB)
JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 1.8-pre2
LWJGL: 2.9.1
OpenGL: Intel(R) HD Graphics GL version 3.1.0 - Build 9.17.10.2932, Intel
GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 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: Yes
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: [Sphax PureBDcraft 256x MC18.zip]
Current Language: English (UK)
Profiler Position: N/A (disabled)