URL indexing problem?

Being new to php & web development about 1 year or so ago i havn't picked up on the SEO tricks yet so please excuse the 'simple minded' comments!

Im trying to get my site indexed properly and each product holding a place in google etc. Im using a series of variables to controll what pages are included in the page, sort of switching the pages dependant on the URL.

EG:

www.canyoudiy.com/index.php?cont=info&info=howto
and
www.canyoudiy.com/index.php?cont=product&product=view&prodID=104
To view another product the only thing that changes is the 'prodID'.


Does any one know if this will cause bad results in the search engines? Most pages still have there own keywords etc controlled by the database and the page title is also dynamic dependant on the database result.