both are important for SEO - the filename in the URL should match up with your title tag. all filenames should be unique. for example

www.coolsite.com/kids-toys/blue-schwinn-bike

not

www.coolsite.com/kids-toys/blue-schwinn-bike/index.php

this latter example would cause you to wind up with Google seeing every page with the same filename index.php

Just to add a little bit to Manischa Mittal's response. I would recommend you spend a couple hundred dollars with SEM and test out several ad variants and see which ad gets the highest CTR. Take the creative winner(s) and use it to build your meta description tag.

Just to add a little bit to Manischa Mittal's response. I would recommend you spend a couple hundred dollars with SEM and test out several ad variants and see which ad gets the highest CTR. Take the creative winner(s) and use it to build your meta description tag.

In my experience, the sequence of the H tags didn't matter at all, but if the H1 tag doesn't deserve to be on top of the other heading tags, I would suspect something may be wrong with your page layout.  I don't recommend more than one H1 tag.per page. The H2, H3 and H4 tags are meant for sub headers. If you don't use the header tags as intended, your pages may be flagged as spam, so use cautiously. I have seen so many webmasters unwittingly abusing these tags, like by putting their brand name in a H1 tag on every single page.