Note that DELL in its wisdom makes a CUSTOM version of some samsung panels, and they ONLY work with DELL computers, so stay away from EBay auctions that say something like, "Dell LTN141P4-L02", because it will work with no other computers.
Here are the 3 possible screens for your laptop. http://www.thinkwiki.org/wiki/TFT_display
IASX16S ID Tech
HT14P12-100 Boe-Hydis (_NOT_ an IPS display)
The 3rd one is not listed on the thinkwiki.org website, but it's the screen I got with my T42 (ATI 9600) in 2006, and it's the screen I threw away when my son jumped on it in 2007, and it's the screen that I (sadly) replaced with the dimmer, pinker, Samsung LTN141P4-L02 about a month later. On paper the samsung has slightly better contrast, but in practice, the Boe-Hydis display is the one that is preferred for SXGA+ 14.1 T42's, T43's, and T60's. http://www.panelook.com/B141PN01%20V1_A ... w_514.html
When IBM Started selling T42's in 2006 with the Boe-Hydis display, there was a flurry of discussion about them on this website. Even though it's not an IPS display, it's nicer than the Samsung displays.