Our family of 4 (19 yr. old and 22 yr. old daughters) are planning a vacation for June. We are thinking about going to Phuket and staying at the Hilton. Any comments/suggestions??

Some points:

pressume you know that June is not the best time weatherwise for Phuket (?), though at that time is not the peak of the rainy season and certainly hotel rates are very cheap at that time.
You need to take heed of warning flags before venturing into the sea to swim, June is not so bad but do note this.

The hilton is across the beach road from the beach which is wide and long, but it is 'across the road' from the beach.

I honestly would say, if you are looking for a Hilton level type hotel to look at le meridien, this is 'absolute right on the beach' and is located in it's own 'cove', techinacly no beach is private but in the case of le meridien it's the only thing in the cove, so you have huge pools ( good if swimming not advisable ) and a great beach. It is south of Patong but easy to get into Patong for shopping, restaurants, entertainment etc.

If you are looking at Hilton type place I think you would find le meridien better beachwise.

if you are 'set' on Karon then the Moevenpick is an alternative, again though across the road from the beach. If you want right on the beach that means the 'Karon Beach Resort' at the sound end. There are also the centara Villas on the hillside at the north end with pathway down the hill to the beach, problem though is the hillside location you need to tuk-tuk to either Karon or Patong, you need to tuk-tuk from Meridien into Patong but it's nearer and cheaper.

Rates in June are lowest season rates of the year, so you might do better with a 2 bedroom suite than getting 2 seperate rooms.

I would add that although June is low season everything is still open and I think it can actauly beat 'peak season' when it can be so crowded, far more expnsive for accommodation and just generaly crowded(!)

I've been in Phuket before in June, and not had a day of rain, so don't worry too much about that.

I've never been a big fan of the Hilton on Karon. It's a big concrete monster in the middle of a long beach. I think JamesA has given you some good pointers on better places to stay.

Also check out the Kata Thani Resort on Kata Noi beach. I've stayed there. Lovely place, many pools, poolside bars, etc. You would have to taxi or shuttle "up" to Kata Beach area (or Patong) for your shopping and restaurants other than the ones at the resort.