Mandrake 9.1 installation can be a bit buggy depending on your hardware setup. If you're running more than 1GB RAM for instance there are different ways to go about initiating installation without hitting snags (such as typing "linux vga=0" or "mem=786M" or "expert noauto").. etc..
Heh. can't say I blame you for being upset some about a failed installation, but keep at it - you'll be amazed at home much you learn by asking funny/strange/straight forward/awkward questions.. and searching stuff on your own.
Keep in mind a couple of things:
-- EACH linux installation is different! (I mean between different users).
-- YOUR linux installation will be tailor-made for YOUR machine!
... unlike Windows, for instance. Microsoft leaves so many options available without user input (assuming that's what the user would want) that this practice creates serious security holes in your OS and thus are more vulnerable to viruses, worms, hacks, crashes, unsightly blemishes, etc..
Ok, after all that - your installation problem. Could you give more details about your machine (include mouse type - USB,etc.. - ram amount, etc)? There are some quarky things about each distribution regarding installations. In some cases the problems are easy to identify straight from seeing what hardware it is that someone's running, other times it could be some strange bug. But still it's best practice to give as much detail as possible before trying to fix a problem - otherwise you may get so many different answers that you'll get even more frustrated..