Just installed version 0.8.1 and when I execute it without any switches I get a modal pop-up with the following error:

"Framebuffer objects not supported (required in this version)"

In the terminal the following prints out:
>$ src/lxdream
The program 'lxdream' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadColor (invalid Colormap parameter)'.
(Details: serial 3335 error_code 12 request_code 79 minor_code 0)
(Note to programmers: normally, X errors are reported asynchronously;
that is, you will receive the error a while after causing it.
To debug your program, run it with the --sync command line
option to change this behavior. You can then get a meaningful
backtrace from your debugger if you break on the gdk_x_error() function.)

Seems like I might be missing some package but I'm not sure what it would be. I did initially get a package missing error when compiling that mentioned esound, gtk+-2.0, and libpng, but after installing the esound dev and libpng packages, /configure finished fine. I've already got a lot of gtk packages installed. 'Make' and 'make install' also went off without a hitch.

If I run lxdream in headless mode, however, I can here the dreamcast boot up music playing. I can get the program to run with the video driver set to null as well, and get the boot up music when I click on the run button.

I am running Ubuntu 7.10/Gutsy Gibbon and here are my system specs:
CPU: Athlon Thunderbird 1.4 Ghz
RAM: 1 gig
Video: Geforce 3 with 256 MBs of ram

See

Short answer: Nvidia doesn't keep the opengl support up to date for anything prior to the GeForce FX. I'm working on a workaround.

Cheers,
Nathan