Not Partitions as it is unable to distinguish one partition from another when everything is on the same HDD. It will also delete any information that allows you to access the other partitions because the Index will no longer be on the C Partition.
The reason the Windows and Ubuntu do not talk to each other is that they are incompatible File Formats so you are unable to read a Linux Partition from the Windows Explorer though with some Linuxes you can read NTFS Partitions unfortunately Ubuntu isn't one of these. While it's OK for a Desktop replacement you can never expect a single CD Install of any OS & Software to have as much as several CD's or a DVD and Ubuntu doesn't have a massive Library of installable programs included at their Home Web Site unlike many of the other Linux's do.
As you are actually using a Debian Based OS in Ubuntu you could look for the software that you require on the Debian Web Site or even pay Mandriva to join the members club and have access to their Software Library where they hold thousands of GIGS of different programs so you will most likely find a replacement for your Windows Programs to run on Linux.
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