thanks so much for your swift response. I am going bonkers here.
I re-downloaded version 2.9.1, unzipped with winrar, replaced the wp-config-sample file with the wp-config I had previously edited (the one which got me to the welcome screen the first time), renamed .htaccess file on the host to .nothtaccess and then uploaded everything with Filezilla (transfer mode ASCII) all to your instructions but, to my acute disappointment, exactly the same error happens!
This has been a tale of woe from the beginning. My first assault on the citadel of the magical 5 minute installation hit a "Parse error" (syntax error, unexpected T_CONSTANT_ENCAPSED_STRING in wp-config.php on line 46) which I eventually got over by ditching the authentication passwords provided by the online generator and substituting them with my own. Soemwhere around this time I also got hit with a virus threat that actually popped up when accessing wordpress own forums - called 'Exploit script injection 370'... this had to be dealt with with by downloading back all the wordpress files that were on my site in order to scan them plus change the site password before uploading them again. Until getting your advice I have been ftp'ing files entirely via windows explorer which is just not up to the task and has meant most of the time copying files manually one by one. (So Filezilla is a phenomenal improvement there at least)
Anyway, I just needed to get all that off my chest, the 5 minute installation has taken three days so far and Im still not there!
If you have read this far thanks, and any further advice you can give will be gratefully received