Dell Dimension 3000 OS Upgrade question?

Windows 7 32 Bit will work at a push if you upgrade your video card and have more than 1 GB of RAM:

http://en.community.dell.com/support-forums/desktop/f/3515/t/19390665.aspx

I personally wouldn't advise upgrading this system. By the time you factor in the cost of the Windows 7 license, Graphics card (onboard graphics below the minimum requirements for Windows 7, you will have a blurry screen) and RAM you have spend about half to two thirds the price of a new computer.

Windows 7 ~$140

http://www.newegg.com/Product/Product.aspx?Item=N82E16832116989

Memory ~$58

http://www.crucial.com/upgrade/Dell-memory/Dimension+%2F+Dimension+XPS/Dimension+3000-upgrades.html

Graphics Card ~$50

http://en.community.dell.com/support-forums/desktop/f/3515/t/19390665.aspx

http://www.amazon.com/Zotac-ZT-40605-10L-nVidia-GeForce-GT430/dp/B005TIEC5C

Total ~ $250. Of course shop around to get more competitive prices...

Not to mention the hard drive (the most likely component to fail) is IDE which is an obsolete interface and harder/more pricy to get spares. The RAM is only DDR.

New Desktop with Windows 8.1 64 Bit ~$330

http://www.dell.com/us/p/desktops?ref=tile4#!dlpgid=everyday-desktops

This will run circles around your old Dell.