|Have you jumpered your hard drive correctly?|
Dell recommend using Cable Select (CS) jumpering.
Does your BIOS setting reflecting your hard drive jumper setting?
advertised disk space is almost always higher than the disk space reported by the OS.
Hard drive manufactures treat 1GB as one billion bytes, while the operating system calls it 1,073,741,824 bytes (1000 * 1000 * 1000 vs 1024 * 1024 * 1024).
Thus the actual OS reported value of 149 GB is about right.
As for 48 Bit LBA, so long as your XP is at SP1 or later you should be fine. However, if you ever installed XP Gold (i.e. without any SP) then you will run the risk of loosing your data.
Primary drive 1 not found
This error suggests that you have set both the master and Slave IDE device to auto in your BIOS and yet you appear to only have 1 Hard drive.
Dell is funny in that, unlike other systems where not having a hard drive equipped and having the BIOS set to auto results in no error, Dell treat it as an error condition as they expect to see a hard drive equipped and are not seeing it when trying to detect it. F1 is like saying "ignore the error and continue" and this is also why your system is working OK. There is no REAL fault just a Dell quirk.
Go into your BIOS and disable the second IDE device and your problem will disappear.
☺ When everything else fails, read the instructions.