question one. i do i upgrade my MySQL to version 5 without loosing my database and how can i connect to an external mysql from a different server..

First Question
Here's how I would do upgrade from older versions:

* make a dump of all your data except the mysql database

* make a separate dump of the mysql database

* uninstall this old MySQL version

* install the latest MySQL version from scratch

* create a separate database for the previously dumped mysql database (e.g.
mysql_old) and restore this dump

* sync the old mysql database with the new one (this might require some
manual work, because the structures will be slightly different)

* when the new mysql database is OK, restore the dump of the data

If you have a chance, try to install the new version on a separate machine,
before you uninstall the old MySQL version to make sure that everythink works.

Second Question:
Connecting Mql server form a Different server

Once you have the database name, username and password, you can connect to the database easily
Note that, depending on where it was created, your database may be on nairaland database servers for instance. If so you would have been given the name of the database server, for instance "db1.int.nairaland.com". In that case you should add an appropriate -h option to the command line:

$ mysql[b] -h db1.int.nairaland.com[/b] -u username -p database-name
Enter password: enter your password; it won't be echoed
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 396905 to server version: 3.23.x

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

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