Upgraded from php4 to php5 leads to wsod in drupal 6

Hi

My problem started when my host upgraded from php4 to php5.
Prior to the upgrade (on php4) I was running Drupal 6 and everything was ok.
After the upgrade I was unable to see admin content or even login because of the wsod.
I could see both admin and custom links but all admin links lead to the wsod
Custom links did lead to content
(it's like a really bad horror move, every time I mention wsod I hear Du du Durr)

As this is a personal development domain I deleted all files and did a fresh install of 6.14,
You can assume my DB settings are correct in settings.php

After examining the DB with Navicat I see I have no tables at all.

And after running the code below in index.php:

error_reporting(E_ALL);
ini_set('display_errors', TRUE);
ini_set('display_startup_errors', TRUE);

I get:

Warning: Table 'drupal_xxx.access' doesn't exist query: SELECT 1 FROM access WHERE type = 'host' AND LOWER('79.74.56.171') LIKE LOWER(mask) AND status = 0 LIMIT 0, 1 in D:\webspace\xxx\wwwroot\includes\database.mysql.inc on line 128

Warning: Table 'drupal_xxx.users' doesn't exist query: SELECT u.*, s.* FROM users u INNER JOIN sessions s ON u.uid = s.uid WHERE s.sid = '579aniaodkivotbjkdc591gmc0' in D:\webspace\xxx\wwwroot\includes\database.mysql.inc on line 128

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at D:\webspace\xxx\wwwroot\includes\database.mysql.inc:128) in D:\webspace\xxx\wwwroot\includes\bootstrap.inc on line 1037

Warning: Table 'drupal_xxx.cache' doesn't exist query: SELECT data, created, headers, expire, serialized FROM cache WHERE cid = 'variables' in D:\webspace\xxx\wwwroot\includes\database.mysql.inc on line 128

Warning: Table 'drupal_xxx.variable' doesn't exist query: SELECT * FROM variable in D:\webspace\xxx\wwwroot\includes\database.mysql.inc on line 128

Notice: Undefined variable: variables in D:\webspace\xxx\wwwroot\includes\bootstrap.inc on line 480

Warning: Table 'drupal_xxx.cache' doesn't exist query: UPDATE cache SET data = '', created = 1253623921, expire = 0, headers = '', serialized = 0 WHERE cid = 'variables' in D:\webspace\xxx\wwwroot\includes\database.mysql.inc on line 128

Notice: Undefined variable: variables in D:\webspace\xxx\wwwroot\includes\bootstrap.inc on line 487

Warning: Table 'drupal_xxx.system' doesn't exist query: SELECT name, filename, throttle FROM system WHERE type = 'module' AND status = 1 AND bootstrap = 1 ORDER BY weight ASC, filename ASC in D:\webspace\xxx\wwwroot\includes\database.mysql.inc on line 128

Warning: Cannot modify header information - headers already sent by (output started at D:\webspace\xxx\wwwroot\includes\database.mysql.inc:128) in D:\webspace\xxx\wwwroot\includes\bootstrap.inc on line 636

Warning: Cannot modify header information - headers already sent by (output started at D:\webspace\xxx\wwwroot\includes\database.mysql.inc:128) in D:\webspace\xxx\wwwroot\includes\bootstrap.inc on line 637

Warning: Cannot modify header information - headers already sent by (output started at D:\webspace\xxx\wwwroot\includes\database.mysql.inc:128) in D:\webspace\xxx\wwwroot\includes\bootstrap.inc on line 638

Warning: Cannot modify header information - headers already sent by (output started at D:\webspace\xxx\wwwroot\includes\database.mysql.inc:128) in D:\webspace\xxx\wwwroot\includes\bootstrap.inc on line 639

Warning: Table 'drupal_xxx.url_alias' doesn't exist query: SELECT COUNT(pid) FROM url_alias in D:\webspace\xxx\wwwroot\includes\database.mysql.inc on line 128

If I deliberately use the wrong db username in settings.php I get:

Site off-line

The site is currently not available due to technical problems. Please try again later. Thank you for your understanding.

Can anybody tell me how I can start again?
As this is a dev domain it's ok to suggest the radical this is not precious.

Cheers