These are basic answers to your questions...
Far as I know that prior rollover would be into an IRA and subject to penalty if removed before 59 1/2. I would imagine your statements from Vanguard would say Individual Retirement Account (IRA).
Your current plan, since employer has some match, would indeed be a 401k. There are some employer 401k plans that allow prior 401k to roll into their plan, but that varies and you need to ask them.
If your question is can your current employer 401k go into an IRA now, I believe the answer is no.
Roth IRA is post tax money and has easier withdrawal rules (while 401k money is tax deferred .. ie. you do not pay tax now on the $$$, but when you withdraw it).
If you have a Vanguard IRA now, you should talk to them or to your current employers benefits specialist.
Thanks guys
At age 59 1/2, one can roll 401K to an IRA. Can you continue contributing to the 401K ?