There’s a subforum titled “CD Freaks Forum Talk” where you might be able to ask about retrieving your old user name (you might have to provide proof that it belongs to you).
As far as burning speed goes, that really depends on the media itself, as the advertised burn speed isn’t always the advised burn speed. There are some 8x discs that are good at 16x, some 16x discs that shouldn’t be burned above 8x, and more. The most telling way to decide how fast to burn a disc (at least initially) is the Media ID, which identifies who actually manufactured the disc (which isn’t always the same as who packaged the disc) as well as the “version” of media it is (somewhat hard to explain, but will make more sense once you start looking into Media IDs).
After identifying the MID, you can look at burn quality scans posted by other users for the same MID to see how fast they’ve burned it and what kind of burn quality they’re getting. Then you can try burning your own discs at a comparable speed and then scanning them yourself to see what kind of quality you get, and adjust accordingly.