Site not being indexed. It has bad URL's. Need coding help.

We have a site that has been online for years. For the last two years our site has not been getting indexed properly and we think maybe the spiders can not crawl it properly. There are over 100,000 items on it. When I try to generate a sitemap I see URL's like the following. [login to view URL] and [login to view URL] Those pages do not even exist but for some reason they are being found when we crawl the site to make a sitemap. The following part should not be at the end of the URL /_098063720522-Mill-Hill-Bugle-Beads-Small-Red-Velvet as well as the /[login to view URL] on the other URL Ive attached snap shots of the sitemap generator and there are 1,000's of malformed urls like above. We need someone to go into the code and fix it so pages like that are not discovered and also fix our current sitemap generator to be functional and setup a cron job so that it runs monthly. [login to view URL]