repair booting process

I fear that my MBR or VBR or what ever is necessary to boot my WindowsXP/Ubuntu/System Restore/Microsoft recovery Console is corrupted.
i have no floppy drive, so how can i boot some diagnostic/repairing software on a cd to fix what ever is wrong?

I do not have another XP computer either, as my 2nd one is vista.

please help. Im in the endless boot cycle.(well i know you can disable auto power on after failure in BIOS, but just to give you a little bit more of an idea of where i am.)

 

You can read (and perhaps fix) the XP partitions with Vista.

Connect the drive to your second pc as a slave if IDE or second drive if SATA.

 

any other options? i have had only limited experience with computer hardware being as i only dismantled my oldest computer, peeked at the inards of the now broken computer, and have yet to actually make my first build(still picking out parts).

parents would fret if they see me going next to this expensive one.

any software solutions? thnx for the suggestion though, i will have to convince them if all else fails.