In a review of Acer TravelMate 2428, they try out Ubuntu on it and it just works.
Read it here
Battery life on the TM2428 while running Linux was about 20% less than in windows. Manually controlling the settings I was able to get about three hours of use from a charge and in 'DVD mode' I managed two hours. There isn't really a DVD mode in Ubuntu (it maxed the CPU speed when playing a DVD – but I found playback was fine at 600 MHz), I had to adjust the screen brightness and CPU speed manually.
I must also point out that the TM2428 ran very nicely with 256 MB when I was using Ubuntu. Linux is famous for being able to make modest hardware look good when it is configured right, and Ubuntu's automatic install and configuration obviously did a good job.