Ok, I know what's DVD-ROM... it's like DVD+/-RW... but what's DVD-RAM? Is it the thing to put a HD-DVD disc into and watch HD movies, or DVD+/-RW can do the same? Should I include DVD-RAM into my new PC?
DVD-ROM is read only, you cannot write to a DVD-ROM (commercial DVD's) DVD-RAM is a type of DVD that instead of using the disc format that we are all acquainted with uses a cartridge style casing which looks a bit like a big floppy disk.
Ok... but it there any internal devices, that could read HD-DVD movies/films? I've heard, that BD-RW (blu-ray) drives can read HD-DVD discs. Maybe same with DVD-ROM? Thanks.
You can certainly buy HD DVD and Blueray drives, although BluRay seems to have an advantage over HD DVD drives at this point in time. You can also buy drives to read both (LG make such drives) if you can afford them. These drives will write Blueray, DVD's and CD's but only be able to read HD DVD's. You'll be looking at around the $500 mark.