Trying to install XP using recovery disks!, proving to be problematic

[JuicyDbase]

I inherited an HP pavilion 7905 from my brother without a hard drive; I ordered restore disks from restoredisks.com because hp said they stopped making them for this model. I got the disks, put in a 20 GB hard drive that was bought quite awhile ago but has never been opened until today. I put the hard drive in, put the first recovery CD in and just as the cd-rom starts to spin up it shows a message "Error! PC system not supported. " I have been working on this thing forever, keep in mind I am not all too computer savvy. And so today I called restoredisks.com about it and they said that the problem could be caused by the fact that this hard drive I put in it is smaller than what was originally put in it. Is there any truth to this?

Also I was trying out this 20 GB hard drive to see if I could install XP on this computer in the first place to see first if this computer works at all so then I might be able to save myself from paying $70 for a hard drive that I can't use. If anyone can help me out here or has any thoughts on the matter that would be awesome. Thanks.

Here are the stats of the computer.

Phoenix BIOS 4.0 Release 6.0.E
Copyright 1985 - 2001 Phoenix Technologies Ltd.
All Rights Reserved

Copyright 2001 by Hewlett Packard Company
Release 3.08
CPU= AMD Athlon(tm) 1333mhz
256M System RAM Passed
256k Cache SRAM Passed
System BIOS Shadowed
Video BIOS Shadowed
UMB upper limit segment address: E61B
Mouse initialized
Fixed Disk 0: Maxtor 91024U4
ATAPI CD-ROM: Hewlett-Packard CD-Writer cd 16f
ATAPI CD-ROM: Toshiba DVD-ROM SD-M1502

Here are the stats of the hard drive, I don't know if this information is imortant or not but I just thought I would throw it in there.

Maxtor
Model: 52049H3
HDA: 13A
PCBA: 05A
Unique: 11A
Code: JAC61HUO
Cylinders: 16383
Heads: 16
Sectors 63
Jumper: j50
Master/single: On
Slave: off
7200 PRM