Yes for sure.
Press Releases are great way to boost your website publicity, and gain some quality backlinks.
Google likes press releases and backlinks from them, so you need to make sure that you will make and distribute some PR's
Only make sure that you don't create and make your press release in the early stage of your website promotion, it should be written and submited(distributed) at the very end of your website promotion plan.
It won't look natural if you have 5 press releases 10 days after you have created your website, I'm mean who have heard for your website only after 10 days, no one know about you and your website do you expect that press know about your website? You should wait until you have build great number of backlinks and then when backlinks are coming from all different places (it means that great amount of websites have heard about you) you should than start writing and submitting PR's.
That will signalized google that something important has been going on about your website and G will pay more attention to your website and it will boost your SERP's for sure.