I have my monitor setup at 1024 x 768 and I still struggle to see the first one. The second one fits on my screen with a little white space around it.

You have to design for your target audience. If you know that everyone who is going to view your site have big screens and can view sites that are designed larger then fine, but remember the bigger the page the longer to download, although miniscule to some might be time consuming to others, not everyone has Broadband connections.

I still advise people to deisgn to 15" monitors and then they are 99% sure they will get their websites displaying correctly for most people.

Personally I don't like the second image, but that isn't to say the people who visit your site won't, the second one is too wide even on my monitor.

Hope that helps.