D.B.
Bowling party : We did this for my son's 4th birthday. We took him out bowling a couple times prior to booking to see if he would even enjoy it and he really did, so we set it up for him. Even the youngest child at his party (2 1/2) had a great time. The alley put bumpers in the gutters so all the kids balls would make it down the alley. I ordered pizza there and brought my own cake. Couldn't have been simplier. The adults got to bowl for free if they were assiting their little one, but most ended up finishing the games for their kids and had SUCH a blast. Also, I made up flyers with instructions for WACKY BOWLING.....i.e. frame one bowl through your legs..frame two sit on the floor and push the ball...etc. You can find the instructions and some suggested ideas for this by googling "wacky bowling rules" on line. That made it REALLY interesting.....the video of the kids and adults doing this was HILARIOUS!
Roller Skating party : My son attended one of these type parties at age four and had a blast. Again, we took him a few times before the party so it would't be a brand new experience for him, but in your condition, let hubby or someone else skate with him. Being able to do this will depend some on the age of your youngest kiddo attending. But at the party my son was at, there was a 3 yr old there who was doing great and was absolutely fearless!!! Roller rinks will have child skates that can be used (think Fisher price kind worn with shoes) and the smaller kids can basically walk/skate along the edge. At this party, all of us adults had a great time getting in touch with our inner child. They also had a thing where the birthday boy and the kids attending the party got center stage at the rink while the birthday song was playing.