HTML-proposals from Google Webmastertools

When I check the diagnostictools i Google Webmastertools I get some proposals for changes in HTML:

1. Identical Titletags - vb puts my pagetitle in front of a lot of my posts followd by the actual title - how do I correct this?

2. Short Metadescriptions - This goes for Blog entries - where do I change this to something more detailed?

3. Identical Metadesciptions - on the surface they look different from each other, but they all point to the user profile page - any possibilities to solve/chabge this this?

Any help/comments would be highly appreciated!

1) [How To] Remove Forum Title from Thread Pages for Long Tail Optimization / Increased Thread Title Relevancy - vBulletin SEO Forums
2) these can be ignored. It's more of a notice than anything else. Unless your site is blog-centrix, i wouldn't worry about it.
3) Again, not a huge issue. Member profile pages likely will never rank as a SERP unless searching for that user's name anyway. Being dynamic content, there will always be dupe titles and thus, meta descriptions that are almost the same, etc and it will happen more and more the larger you get. Just keep in mind these are only warnings, not errors, and will not effect your site's overall ranking in any negative way.

Thank you, Brian - your answer was most helpful :-)