1..yes, will work fine, just a touch slower than it should be
2..2k pro will handle the new hardware just fine, my homemade only had a reinstal when I swapped to xp for a while, the original win 98 install patched and updated has been ghosted and swapped over on each upgrade and apart from one minor niggle with an AGP bios driver that could well have happened on a fresh install, no problems at all.
3..get rid of the DVD drive, 2x is pants and the new writer will play dvd for you anyway, and haveing 2 writers can often be useful (archiving for eg), why chuck a good writer and keep a slow dvd player??
just my 2 bobs worth
Mentor.
1: P4 hyperthreading 3ghz, 1gig mem, 2x160gig hd`s, ATI radeon 9800 pro gfx, 6 way surround sound, 2: AMD 1.2ghz, 512mb ram, FX5200 ultra gfx, stereo 16 bit soundblaster, ups.