HELP INSTALL: WinXP Pro, Memory, HDD, DSL

CURRENT SYSTEM:  Dell Dimension 8100 with Intel P4; WinME; Mem = 256 meg; 60G. Ultra ATA HDD; 16X DVDROM drive; 16X/10X/40X CD-RW drive; 3.5in. floppy drive; 56K dial-up service.

 

I want to???
+UPGRADE to WinXP Pro
+INSTALL 1GB. more memory
+INSTALL 2nd HDD = 10GB 3.5in. enhanched IDE. (for back-ups only)
+INSTALL DSL service

 

If I install DSL before WinXP, it will make downloading SP2 much faster OR will I have to re-install DSL after WinXP?  Will WinME handle 1.25G memory OR must I install WinXP before the extra memory?  If I install the 2nd HDD first, can I back up my current data on it before installing WinXP OR should I burn CDs for back-up and install the 2nd HDD later in the event I can't access the drive?   I assume there is a "most efficient" order in which to all this.

 

I have stock-piled extra coal to keep my old Dell Dim8100 fired up.  My hammer and pry bar are at the ready to crack open the tower.  A fresh can of coffee and a new bottle of aspirin are sitting on the counter.  The WinXP compatability-erator says "Good Luck" (I didn't tell it about the coal) so with a shaaaaaky hand I ask, where do I start?