Originally my gateway laptop developed a flickering screen. Gateway help told me to re-seat the battery and memory. After I did this the computer would not re-boot. The power light comes on but nothing happens.

Take a close look at the battery contacts on the battery and on the laptop itself.
If it's under warranty, get it back to them as soon as possible.

This happened to my e-machines desktop that was running windows98. I thew it in the garbage.