Hey All , Im in need of some help

I have a laptop thats playing up. Several days ago the laptop shut itself down and since then windows startup then just gets stuck on the welcome screen ( just before the desktop screen) . I have tried safe mode , last known good configuration but still gets stuck at the same point.

When my PC used to have problems with windows I remember I could stick a diskette in and boot up , doing this then takes me to dos mode for scandisk , repair.

Since the laptop does not have a diskette drive, how can I get it to boot into dos mode ? or can anyone suggest any better ways to sort the laptop out.

I have a real license of windows XP Home edition with license key but since it is oem i didnt get a windows cd with it .