Need advice regarding purchase of DVD writer.

[liordeck]

Hello all,
I am new to DVD writers, hardware and software.
I have a few questions, please bear with me:
1. Do DVD writers today support different formats? I.e. is there a DVD writer which supports 4.5GB and another which supports 7.2GB for example?
2. Does a DVD writer require a different software for burning than a regular CDRW?
3. Are DVD writers capable of overriding CDRW protections like SafeDisc2, Securom, Laser Lok, read errors and such?
4. Are DVD writers today capable of doing the same for protected DVD's?
5. The most important concerns when buying one... please tell me what they are.

Thank-you for the patience.