5.0 upgrade

Hi!
We need to upgrade from Drupal 5 (launched in 2009) and since we have never done this before I would appreciate any advice or guidance on what I believe our options are.
Option 1) Just do a straight across the board upgrade.
Option 2) Do an upgrade and make enhancements that we have identified as an organization and include our enhancements in the RFP.
Option 3) Hire a developer to do a 2-3 week intense modernization of website proposal. Cost is a concern with this option.

Hi All,
what is the best way to upgrade the mult-site with single code-base because now when i upgrade the site from 5.x to 6.x it only upgrade the main site where i started the upgrade process with update.php but when i go to site2.com/update.php , it does not upgrade anything site specific tables.

Thanks,

Hello,
Looking for some input on a problem if anyone has an idea off the top of their head.
I've tried upgrading a test version of my site from drupal 4.7 to drupal 5.1 several times now. Each time, the update.php script stops about halfway. Then I have a site that seems to be working fine except it doesn't show any columns on the side (left or right), meaning no blocks. When I hit admin/build/block, this is what I get...(see below)
Any idea what I can do to fix this? The message i get on the block admin page is Greek to me....