Ok so may site apparently has numerous html errors. Should I go through them all and correct them? Im not really sure of the benefits of correcting them and the cons of not correcting them, so any advice would be great Thanks
It's similar to speaking English. If you speak with lots of errors, most people can still understand you (e.g FF IE etc), but some of us (e.g browsers like Lynx) will simply refuse to communicate with you. Make it easy for spiders and text browsers to read your site, use valid code whenever you can. But don't make it your life's work Some things simply won't validate (standard Flash embed code etc).
your code wll not have all of those errors... The validator works the code line by line so if some thing isn't closed then the next thing shouldn't be there so that's two errors. you can have one error but the validator will tell you there are hundreds... TIP: work from the error that is first in the list!!