should I register the product's name (a commercial software)?

For these questions the legalities will vary according to your country. You don't say wehere in Europe you are, so in the USA, here are the answers to your questions: http://www.uspto.gov/faq/trademarks.jsp You should look up a similar list for your country. Maybe there is a single set of law for all the EU, so maybe that is the correct way for you to search for it.

Anyway, the laws in your country should be only slightly different from the USA's. There has been a push for a long time to standardize intellectual property laws internationally, and so laws vary in relatively small details, such as the time length of a patent's validity.

The WIPO (World Intellectual Property Organization) is the place to look for international IP issues: http://www.wipo.int . You should pay attention to the international aspects of your situation, such as what protection you can expect for your trademark if you only register it on your home country.

In other words, it's fine to do this research without a lawyer, you just have to spend some good time on it.

In the uk = Intellectual Property Office - http://www.ipo.gov.uk/tm.htm

A good explanation on what is deemed an acceptable trademark:

To be accepted, your trade mark must be a distinctive word, logo, picture or other sign that will clearly identify your goods or service from those of other traders. Made up words, logos or pictures are normally distinctive, unless they have become customary in your line of trade.

If this type of thing is important to you, then get the trademark. Or as my kids would say, "if you love it put a ring on it."

Regarding Europe, there is a way to file a single trademark application directed to coverage in all of Europe. The application, called a "Community Trade Mark" application, is filed with the Office for Harmonization in the Internal Market (OHIM), sometimes colloquially referred to as "the European Trademark Office." The cost to file such an application, again assuming only one trademark class, may be estimated at around $2000, including government fees, fees to a European trademark firm, and fees to one's US trademark counsel.

Good luck.

First off, I'm not a lawyer and this doesn't constitute legal advice.

With that out the way, you don't have to register the name of your product. But if you are going to be selling it commercially, I would go ahead and file applications with the USPTO and the IPO in the UK.

If you don't have trademark protection and another company claims you are infringing on their trademark, you will probably be forced to change the name of your product and at worst be liable for damages.

A recent example would be all the applications and services that were infringing on Twitter's name.

Twitter registered their Trademark April 26th, 2007, but was first used in commerce on Aug. 31, 2006. So they waited a full 8 months to register their trademark.

But last year Twitter warned companies that were using it's now trademarked name as part of their own name or service would have to change their names. All of them did. Some companies were able to still keep their name even though it was similar (eg TwitPic).

You can file an Intent To Use (ITU) application with the USPTO office if you want to secure the trademark now but your product isn't ready for release. But it will cost more money to file an in use application.

It all comes down to your level of risk. Register the trademark now and sleep at night or wait a few months until money starts coming in.

It may be best to ask a lawyer, but I understand that you don't need to register Trademarks and Copyrights. The fact that the name is public constitutes a trademarked name. If you ever get into litigation it will help to have it properly trademarked, especially to set the date on which you made it public. In your case, having over 200 beta users gives you 200 witnesses that your name is in fact public.

You don't necessarily need an attorney to file it if you cant spend 2K. You only need $325 and you can do-it-yourself.

Search if the name exists: http://tess2.uspto.gov/bin/gate.exe?f=tess&state=4010:grc538.1.1 Apply online: http://www.uspto.gov/teas/eTEASpageA.htm

Good luck