Just back and went to Universal twice. Very easy to get to. We stayed at Wilderness Lodge. The day before, we called Mears to arrange a time. We were given a few options (8:15am, 9:15am, etc...) We just gave our name and number in our party.
The next morning, the big mears bus (full size bus - bigger than the local disney buses) pulls up right on time. We were the first ones on the bus. $14 a person, cash or travellers checks. (altough the driver wasn't able give change for the $28 transaction from $40. Ended up giving him $30 instead. I would recommend you have exact cash in case it would be a problem) From WL, we stopped at 2 more places (Poly and Port Orleans) and then went to US. Total time was probably 45 - 50 minutes or so.
When you pay the driver, he will give you a return voucher. You need it to return. You can either schedule a time when you first call to reserve it, or you can call from the park. (number is on the voucher) In our case, the park closed at 6:00pm. We ate dinner at 6:15. We called right when we were seated and were given the option of being picked up at 7:30 or 8:30. We chose 8:30 for a nice relaxing dinner. A van picked us up in the same place we were dropped off.
The next day, my wife felt ill, but we dicided to go to US at the last minute. Because it was last minute, we didn't call Mears, but took a taxi. From WL to US, about $40 each way. Much more expensive, but also much quicker and didn't have to worry about any schedule (which was good because we left earlier than anticipated)