Installing XP Media Center Edition - Will Diag and DSR Partitions Be Right?

Well, my title summarizes my question pretty well. 

The story: I have a very nice Dell 8400 with MCE 2005 on it.  There is some kind of bug in the OS that has prevented SP3 from being installed and is slowly destroying the system's functionality.  This summer I spent many long hours with Dell and uS support trying to repair the crash that happened after SP3 was installed.  Not much worked.  We ended up trying to do over-the-top install of XP (i.e. not a clean install), installs of .Net, SP2, and finally SP3.  Everything was fine until SP3 was installed, then the OS crashed, only to limp along in safe mode.  Our final solution was to do a clean install, which I hesitated to do, since SP2 was working well and I could do without SP3.  Now my warrantee is expired (and I get no free help!)

Now my system has deteriorated with symptoms similar to what happened before, with XP booting up with functionality that degraded over time.  I have attributed that to a hard drive that has reached the end if its life.  However, the hard diagnostic available thru F12 doesn't find errors, nor does the diagnostic partition program.  All the tests for the system and hard drive have been run and pass.

Therefore, I have bought a new hard drive and want to install it as a replacement for my original drive.  I'm ready to do a fresh install of XP and install all the .Net and SP upgrades.  However, I'm uncertain what will happen with the diagnostic and DSR partitions.  I know I can download the diagnostic program.  But I don't know how to make a multi-boot disc, and coordinate the function keys with the BIOS and / or disc etc. etc. etc.  I'm less certain about the DSR, if I would end up with one or not.  I'd really like to find a way to use the DSR, since that seems to have all the system configuration set up for my PC.  So, I'd appreciate any hints, how-to articles, or whatever advice y'all may have.

Thanks in advance!

Dave