If you have access to another computer, go here to get a file that will make you a boot floppy or CD:
There are more extensive "rescue" disks such as Bart's PE or Ultimate Boot CD for Windows, but you need the files from an XP CD to make one, and as you say you have recovery disks, you probably don't have one. Or you could install your drive as a slave in the second computer and get access to your data that way.
*However* -- before you go ahead and do the recovery, it would be well worth posting again with the exact error message you're getting. It may be that your boot.ini file is damaged or corrupt and that could be easily fixed and save you having to do a complete reinstall.
Hope this helps :-) Let us know how it goes.