Applications quit unexpectedly - help!

Hi there,
I recently had to get my macbook pro fixed as it was giving me the blue screen of death and getting hooked on startup and would completely freeze. After reinstalling Leopard 10.5 and updating all software I noticed that my system wasn't quite right. On Tuesday, I trying opening iTunes and it told me that I needed to update to quicktime 7.5.5 so I did. Ever since, I have been getting application quit unexpectedly messages for all of my mac applications and the only applications that work are firefox (thank goodness) and Word.
I have searched tons of forums trying to figure out how to fix this and when I get to the end of the threads, either there is no solution or what worked for someone else...hasn't worked for me.
Any words of wisdom? I'd really appreciate your help!
Thanks,
Geo

Macbook Pro 3,1 - Mac OS X Leopard Version 10.5.8 - Processor 2.4Ghs Intel Core 2 Duo - Memory 4 GB 667 MHz DDR2 SDRAM

Start by checking your Applications > Utilities > Console logs to get some idea of whats causing it.

Hi Kaveman, thanks for your input. The first application to quit after starting up is Spotlight. "Application Spotlight quit unexpectedly". Here is the console log crash report for it which is all gibberish to me:

Process: Spotlight [191]
Path: /System/Library/CoreServices/Spotlight.app/Contents/MacOS/Spotlight
Identifier: Spotlight
Version: ??? (???)
Code Type: X86 (Native)
Parent Process: launchd [103]

Date/Time: 2011-11-10 21:47:55.861 -0500
OS Version: Mac OS X 10.5.8 (9L31a)
Report Version: 6
Anonymous UUID: FA616219-9E10-4F7B-8B5A-E3B9E4085C5D

Exception Type: EXC_BAD_ACCESS (SIGBUS)
Exception Codes: 0x000000000000000a, 0x0000000096efe7b4
Crashed Thread: 0

Thread 0 Crashed:
0 dyld 0x8fe22114 strcmp + 84
1 dyld 0x8fe05f71 dyld::loadPhase4(char const*, dyld::LoadContext const&, std::vector<char const*, std::allocator<char const*> >*) + 161
2 dyld 0x8fe06445 dyld::loadPhase3(char const*, dyld::LoadContext const&, std::vector<char const*, std::allocator<char const*> >*) + 773
3 dyld 0x8fe069ac dyld::loadPhase1(char const*, dyld::LoadContext const&, std::vector<char const*, std::allocator<char const*> >*) + 156
4 dyld 0x8fe06a73 dyld::loadPhase0(char const*, dyld::LoadContext const&, std::vector<char const*, std::allocator<char const*> >*) + 67
5 dyld 0x8fe06bd2 dyld::load(char const*, dyld::LoadContext const&) + 130
6 dyld 0x8fe06df8 dyld::libraryLocator(char const*, bool, bool, char const*, ImageLoader::RPathChain const*) + 72
7 dyld 0x8fe0f22d ImageLoader::recursiveLoadLibraries(ImageLoader::L inkContext const&, ImageLoader::RPathChain const&) + 557
8 dyld 0x8fe0f13f ImageLoader::recursiveLoadLibraries(ImageLoader::L inkContext const&, ImageLoader::RPathChain const&) + 319
9 dyld 0x8fe1057e ImageLoader::link(ImageLoader::LinkContext const&, bool, bool, ImageLoader::RPathChain const&) + 62
10 dyld 0x8fe051ae dyld::link(ImageLoader*, bool, ImageLoader::RPathChain const&) + 158
11 dyld 0x8fe07acf dyld::_main(mach_header const*, unsigned long, int, char const**, char const**, char const**) + 2831
12 dyld 0x8fe01872 dyldbootstrap::start(mach_header const*, int, char const**, long) + 818
13 dyld 0x8fe01037 _dyld_start + 39

Thread 0 crashed with X86 Thread State (32-bit):
eax: 0x00000854 ebx: 0x8fe057eb ecx: 0x935574dc edx: 0x00000085
edi: 0x96efe7ac esi: 0x935574dc ebp: 0xbfffd2f8 esp: 0xbfffc1f4
ss: 0x0000001f efl: 0x00010212 eip: 0x8fe22114 cs: 0x00000017
ds: 0x0000001f es: 0x0000001f fs: 0x00000000 gs: 0x00000037
cr2: 0x96efe7b4

Binary Images:
0x8fe00000 - 0x8fe2db43 dyld 97.1 (???) <458eed38a009e5658a79579e7bc26603> /usr/lib/dyld

Crashing Spotlight is almost impossible to advise. If you just got something fixed I'd take it back and see if they can't look at this. It sounds like corrupted files, and that could well have happened when aborting the startup problem.