if you are installing vista in a multi-boot environment (e.g. with XP or server 2003 on a separate partition or disk) you might run into the issue that only vista is booting and no other entries are shown in the boot menu.
since vista is not using boot.ini anymore like "older" windows versions did. vista is using the boot configation data (BCD) store for this.
editing this is more complicated than just editing boot.ini in the past.
but i found a nice tool to easily manage (add/remove/edit other operating systems) the BCD store: vista boot pro
with this i could easily add my windows server 2003 system on my second partition to the vista boot menu.