The Debian installer always gave me problems. For desktop usage, I have had a lot of success using Knoppix as an installer. Simply boot up the Knoppix CD, hit ctrl+alt+F1, enter "knoppix-installer" and follow the directions. It is simple and has worked flawlessly for me on 3 machines. The main limitation is that it only installs to one partition "/", but you can create and move partitions after installing. A detailed review is here: http://www.distrowatch.com/dwres.php...review-knoppix
Another good option is to try the Debian-anaconda installation CDs from Progeny. ISO images are available here: http://platform.progeny.com/anaconda/
Be sure to read the errata as the software is still in alpha. However, it can work if you follow the directions in the errata. The anaconda version installs a standard Debian-Sarge with Gnome and XFree86 4.2.1. Knoppix installs a testing/unstable mix with KDE and a lot of custom packages (including Xfree86 4.3). Of course, after it is installed, you can use apt to add or remove anything you like. Good luck.