Stepping through what you have posted;
1] Onboard SATA hard drive not present. I am no expert but if your BIOS shows a "Bootable hard drive", then it boots from this, and then XP discovers the SATA hard drive drivers, and continues to load the operating system. That assumes that your OS is installed on a SATA hard drive. So if all that is true, then the message in the BIOS is probably not a problem.
2] IDE hard drive not present. Not sure. But again, if your system boots up OK then nothing to worry about.
3] USB Floppy drive not present. Does your system have a floppy hard drive connected by USB? If not, then it is not present.
Does that help?