Your card is detected and a driver is installed. It says i915. I am not
familiar with Intel drivers. My card is Nvidia.
Obviously it does not do the trick or you would have the resolution that you
want. It is the closest match is my guess.

I went to the Dell site and found no driver for your card (Brookdale).
support.dell.com/.../devices.aspx\
temID=DIM_PNT_CEL_2350&os=WW1&osl=EN

You can compile your own, but that prospect may not sound encouraging. This
is how:
www.lesbell.com.au/.../16b775253fa0\
d477ca256d07001cd06c?OpenDocument

This has not been a banner year for open source and Intel display drivers.
Earlier in the year many Intel and ATI users were left in the cold when
those equipment manufacturers were late in providing drivers for the kernel
included with Ubuntu 9.04. It dragged on for months. Not being affected I
did not keep up with those developments. Don't get me wrong. Intel graphics
cards are great, just not well supported.

Perhaps someone with a Dell Dimension and Intel display driver could add
their two cents.