FWIW (probably not much), I'm -0 on this suggestion. As others have pointed out, bookmarks (browser or social) work very well for saving things to read later, not only on HN, but on any website.
While an up-vote already saves links, I wouldn't suggest up-voting things you haven't yet read, so I don't think that's quite the right answer to your request.
also, there are many companies that offer bookmarking services that integrate really nicely into the browser and only require a click of a button; you can give one of those a try.
At the moment I am saving comment links etc. for great comments in a versioned text document - it's not great :(
We already have the best-of-HN list: http://news.ycombinator.com/best . However, the bad news is that it's not normalized to the ratio of views to up-votes, and since score magnitude seems to be positively related to HN population at the time of submission (not to mention time of day, day of the week, etc.). At the least, it's heavily skewed towards recent articles.
In general I believe the voting systems on this site and others to be pretty crude and problematic, and while it works for finding a reasonably interesting set of articles, I suggest extreme skepticism towards looking at the best-of-list as "a good reference set of important things to read when starting a startup" any more than going through the Slashdot archives is a good thing for a budding systems administrator.