Vista - I can't open my excel files. Need help urgently!

I'm using SONY VAIO VGN-CR35S/P on Vista Platform with MS Office 2007 license, I have bought in April 2008. It's been doing fine to me till lately I've noticed that everytime I opened .xls (last excel version) or any excel files with Macro, I can never open my .xlsx files on the computer.

I assume that the problem might be from the document recovery in the left box of excel file that i try to open. This is the error message I've gotten:

Problem signature:
Problem Event Name: APPCRASH
Application Name: EXCEL.EXE
Application Version: 12.0.6331.5000
Application Timestamp: 48fa2869
Fault Module Name: OLEAUT32.dll
Fault Module Version: 6.0.6001.18000
Fault Module Timestamp: 4791a74f
Exception Code: c0000005
Exception Offset: 00004580
OS Version: 6.0.6001.2.1.0.768.3
Locale ID: 1033
Additional information about the problem:
LCID: 1033
Brand: Office12Crash
skulcid: 1033
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What should I do to fix the problem? I would like to get the very important info in that excel file I look forward to your help. Thank you.