We've been to PV a half dozen times. Where will you be located?
There's two zones within PV itself that appeal to tourists, and they are on either side of the river that bisects the town. The first is the Malecon area. The Malecon is a long promenade along the ocean (actually the Bay of Banderas). There's lots of shops, restaurants and clubs along it that face the water. Plus there's more such places for a couple of blocks inland.
The places in the Malecon tend to be big, lively and touristy. There's a Hard Rock Cafe and a Planet Hollywod, plus plenty of night clubs. The clubs get hopping late, and go into the wee hours. They can get crowded, and generally feature loud music and drunk tourists. We went to a place called "The Zoo" on our last trip. We got there early, during happy hour. Women drank for free, and men got two for one on margaritas! Speaking of drunk tourists....
The other interesting part of the city is the Playa Los Muertos area. This is the older section of town, and the bars are smaller and less fancy. The prices are correspondingly less, too. There's lots of little cafes and coffee shops too. And PV's best restaurants are in the old section of town. We like Balam's, Adobe Cafe, Daquiri Dick's, and many others.
The Playa Los Muertos beach itself is a lot of fun. You can sit under an umbrella all day while waiters bring you drinks, chips and salsa. And as I said, it's surprisingly cheap. There's plenty of water activity, with parasailing, fishing boats, jetskis, etc. available right from the beach.
Warnings for PLM are that it gets really crowded with locals on the weekend. Weekdays are better. Also the beach vendors can be overwhelming. It doesn't bother us; we just say "no, gracias" and they move on. I know that some people get tired of it, though. But vendors come around with fresh bakery in the morning, which we like. And when the fishing boats return with their catch around noon, the fish get cleaned and grilled right near the beach. Vendors then come around with "marlin on a stick" and we always get some of that too.
Other things we've done... There's a few places out in the jungle where you can eat and drink, and swim in the river while you're there, and these are an awful lot of fun. There's Chino's, Chico's and Eden. We went to Chico's but I think they are all pretty much the same.
We also take a party boat every trip. We usually negotiate something with one of the guys on PLM beach. {{Actually, my brother usually buys pot from one of them, and I think we get a special junkie deal on the boat trip.}} I (vaguely) remember one where we left in the morning, had breakfast on board, went out a ways and snorkeled, had lunch in some remote village and finally got back around 6:00 PM. There was an open bar the entire day, too. Cost? $23 per person!
Lastly... PV's people are very friendly. But if you run across one that's really friendly, he's probably a timeshare vendor. Just keep walking, unless you want to spend a half day listening to a timsehare pitch (and trust me, you don't).