Website Crawlability Issues
Craw ability issues can play a vital factor in optimization. For example you have a javascript drop down menu, and all your high authority links are pointing into your home page. If this is the case and your inner pages don’t have no links going to them from your home page, or other websites then the page rank will be very low if you even have any of course. You want to make sure that your site structure can be crawled efficiently. I would never suggest using a javascript drop down menu for navigational purposes or a html select drop down menu.
The best navigational menus to use is a CSS menu that is search engine friendly you can find numerous tutorial on them online. As long as your code is reading properly in the source such as your <a href tags you should be fine. A great way to find out if your website is crawable by search engines is to use a text browser. A good text browser would be Lynx Text Only Browser this is an outstanding browser to use to check to see if your site is crawlable. Even Google recommends using it.
Just like I stated earlier the thing is with your links not linking appropriately to each others will cause the page rank not to flow correctly. And for any one that don’t know page rank is what ranks you higher in the engines well it comes to tell how important a page is anyways. So give it a try and test the browser out and make sure your site is craw able if not then I would suggest getting it fixed asap before you do anything else to your website.