If you order, get it directly from toshiba. BB pc guys are about the same level as their mobile install guys, shitty.
Just make sure no matter what you do, always make backups. If anything happens and you have to take your computer anywhere, chances are you'll get it back with the origional software and everything you have wiped clean.
as to core duo vs core 2 duo, I believe core duo is dual core 32 bit where core 2 duo is dual core 64/32 bit. Unless you're running a 64-bit os, you're not going to notice ANY difference between the core2duo or the coreduo
Vista will be several hundred dollers. I think last time I checked, the non-basic version was around 350-400 bucks. You don't want Vista Basic. It has all of the pretty stuff cut out. Also, if you're getting Vista when it comes out, MAKE SURE you have 1gb of ram and the intal 950 graphics or higher, or descrete (ati/nvidia) graphics. Otherwise, you'll be stuck in non-pretty mode.