E1505 Reinstalling MediaDirect on XP

I have upgraded a new (March 2007) E1505 from Vista to XP Pro.  Two times, VISTA stopped working for various reasons soon after Microsoft updates were installed, and I wasted too much time screwing around with it.  When I installed XP pro on the E1505, I DID NOT repartition the 160GB Hard Drive, I only let the Windows XP install program reformat the existing C: partition for the OS.  I left all of the other partitions alone - maybe I will get Norton Ghost in order to save my XP image to the partition that VISTA used for its factory restore image later.  This is what the hard drive looks like now (Data from Western Digital Lifeguard Tools):

 MBR Partition Table:
 - Type -   Bootable    -- Size --    Description
 222(DEh)       NO           57 MB    Dell Utility Partition (FAT16)
 NTFS           NO        10738 MB    RECOVERY [D:]
 NTFS          YES       147106 MB    160GB Drive [C:] Windows OS
 221(DDh)       NO         2146 MB    MEDIADIRECT (FAT32)

When XP is running, if I press the MediaDirect Button, I get this:
"Unable to launch Dell Media Experience. Please install the software and try again."  If the PC is off and I press the Media Direct Button, it appears to start up, (a video page appears), but nothing ever happens such as a menu, etc.
The Application CD for Media Direct 3 sent with the original VISTA system was P/N UP137 Rev A00.  I see that since that time, there is an urgent update, R157499.exe, Rev A05, shown on my Dell XP downloads page that should be installed to fix MD 3.0.  My questions:

1) Is this CD the correct one to use/should I/do I need to use it, or will running R157499.exe do it all for me?
2) What is the best way/order of installation for me to follow in order to restore full functionality to MD?
3) Is the newest Dell Media Direct Repair Utility (R121517.exe) even needed in my case since my MEDIADIRECT partition hasn't been touched?
4) Can this reinstall/fix be done without destroying my Win XP installation?