Who I have the same questioned this topic

I will be travelling to the UK.  I have Verizon service on an iPhone 4S.  My intention is to switch out the SIM card when I get there after purchasing a new SIM card with a UK phone number to give to friends and family to call me on.

Questions:

1) According to what I have read, my Verizon 4s phone should be unlocked and I should have no trouble removing the SIM card and temporarily switching it to the new UK SIM card while I am over there.  Is that right?

2) The apps, etc. that are on my phone and my emails, etc. should all continue to work even though my phone number will have been temporarily changed, right?

3) AND, one other issue totally unrelated - my phone suddenly stopped viewing in sideways (landscape) view and I didn't do anything to settings nor can I find any settings that would adjust that.  Any thoughts on what that might be?  I may need to post that question with a different subject line but thought I would at least ask it here.

Thanks in advance for answers and advice!