I'm going to register a few domains and setting up websites on them. I've read whatever I've found out about that, however there are some issues I've not been able to find recommendations about. Here they are.
Reliable mail address for communications from your registrar
This seems to be paramount: you need a mail address you will not risk losing. Thus, you'd better use a reliable (paid) mail service (for instance: fastmail.fm). Right?
Privacy
Your phone number will be publicly available, therefore you'd better buy another cell-phone card and use its number, so that you will not be reachable by random people.
Some registrars offer to hide your contact info, but then they will own of your domain. This is not recommended, since ownership of your domain is a must. Right?
Switching hosting
As soon as I register the domains, I'd park them. Will I be able to switch hosts at will from then on? I think I could end up using a VPS for maximum flexibility, but I'd prefer starting with a cheaper - maybe free - option (with limited available services).
Thank you very much.
EDIT: I'm not interested in parking domains to sell them afterwards. I'm going to use them eventually, but currently I'm a newbie at web programming and I'd just like to acquire them ASAP (as I've seen it's recommended).
2) Privacy: I really didn't mind having my information theoretically out there until the first time I got a call from a Romanian high school student asking me for advice on setting up his software business. I actually don't mind giving advice to people, but the 4:30 AM wakeup call was unanticipated.
Private registration does not mean "the registrar owns your domain". It is quiiiiite the racket for GoDaddy et al, but the overwhelming majority of large-scale domain buyers I'm acquainted with avail themselves of it.
Hosting: Orthogonal to who you register the domain with. All registrars will let you change the DNS settings for the domain to point to your DNS server of choice. For example, GoDaddy has all my domains pointed at ns1.slicehost.net, etc. From there I configure what machine the domain resolves to by changing DNS records at Slicehost.
Note that changing DNS records is essentially at will but it is not instantaneous. If you do it to a production website you have to take some care to avoid service interruptions.
Edited to add: You exhibited some interest in parking. I would not get your hopes up -- the domains which are available for registration these days generally do not generate the level of type-in traffic to make appreciable amounts of income. The folks who make money through parking do it because they control super-premium domain names or portfolios with 100k+ domains in them. Given your current level of understanding of the field, you're not nearly ready to make money merely by possessing domains, so you can get away with not worrying about this factor at all. (Instead, I would suggest putting up a mini-site on the domain and then putting at least one decent link to that site ASAP to start it aging like a fine cheese. This is mostly for SEO reasons.)