The tweak requires a little registry editing, so if you're uncomfortable with rolling up your sleeves a touch, this might not be for you. That said, the results are great, offering a much better preview of your open Windows, especially on large monitors. CyberNet walks you through the process step by step, so despite the registry hurdle, anyone should be able to do it..
Bigger Thumbnails for Vista's Alt-Tab [CyberNet]
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