Hi,
someone would be happy to try helping, but without knowing what error you get, and what exactly your PS1 code/string looks like, it's difficult to speculate on what the problem is. Please show what you've got in the .bashrc, and copy+paste for us the exact error message from your terminal to your next post.
Note that when posting pieces of code, and stuff from your terminal, please use code tags around the data. See here for details:
http://www.phpbb.com/community/faq.php?mode=bbcode#f2r1