At present i m looking to register a two word domain name. I found a two word domain name that I really liked and could only get one of the following extension/word combinations.

one-two.com
onetwo.info
onetwo.us

which should I choose?

It is straight .info or .us worth more than a .com with a hyphen in it.

Choose onetwo.info. As far as I know SE don’t like hyphen. It can cause some issues later indexing the site.

Yes, onetwo.info will be best.

i m disagree with you. According to SEO gurus hyphens are perfect for search engines, so you might want to grab the one-two.com version for better SE optimization.

Its Depends on what you want to do with it.

I would definitely choose the first one , .com is more valuable

Depends on what you want to do with it. If its a High OVT ranking combination of words, theh go with .com.

If your website for an informationtional product, place or thing, then choose .info

if you plan to develope a site for the US market, then .us otherwise .com