First off, there is no way to destroy your hard drive by doing something wrong in Linux. When worst comes to worst, you will just have to reformat the drive.
When you're installing Suse it will ask you where you want to install the system (well, maybe not in so many words). It will ask you if you want to automatically partition you drive or if you want a custom configuration. While Suse should detect that you have Windows and leave it be, you should probably choose the custom configuration. If you have two partitions, you need to install it on the FAT32 partition (although the FAT32 format will be erased as well as any other information on this partition). Your Windows partition will not be touched. This should be all you have to do.
Please also check this out: Suse Documentation
->Startup Guide. All it took was a simple Google search to find this. Suse is a very popular distrobution and there is a lot of documentation on in.
This is a good place to ask questions, but please do some reading to answer your questions like this, after all, it is a very broad question. I'm not trying to discourage you though, just help you be able to answer your own questions, because this skill will definantly come in handy if you are planning on using Linux very much.