Glenadough

Glendalough is beautiful and you won't regret going. For nearby stops, I recommend Powerscourt which has lovely gardens and a waterfall. Good for leisurely strolling. You can also take a nice stroll to the lough itself at Glendalough. My favourite thing about the site is that St Kevin went there to get away from everyone but they all followed him there anyway. If you want to take the scenic route, you can drive along the Military Road. Good luck with your planning!

This is great, thank you so much! Any recommendations for a place to eat anywhere along the way? Would love to visit an quaint pub or restaurant for lunch or dinner.

Glendalough is wonderful. The area around the ruined cathedral and round tower are always busy and it is definitley worth following some of the walking trails - especially round the upper lake to reach the quieter areas . There is a map and information about some of the different short walks here.

You could easily spend half a day here and don't miss the Visitor Centre.

As was mentioned, the Old Military Road (the R115 on the map) is an altogether pleasant way to get to the monastic site from Dublin. It meanders thru rolling countryside and is dotted with scenic pull-offs and photo ops. It has a fascinating history too - do a Google search to see why it was built in the first place.
Near the village of Glencree just off the R115 is a small German military cemetery from WW's I and II. It's a beautiful place - nestled in a little grove with a small stream running alongside, and there's a small path leading up the hill next to the stream leading to an old Mass Rock. We thought it one of the most evocative places we visited in Ireland. There used to be a cute little tea room in the village as I recall.
With a car I'd suggest that you get an early start in order to arrive at Glendalough before the opening of the Visitor Center at 9:30. That way you'll be ahead of the tour buses and day trippers and likely have the site all to yourselves - making it a truly magical experience.
There are a number of very pretty walks in the vicinity of the monastic site itself, including one that proceeds uphill to a boardwalk that eventually circles the valley featuring terrific views of the surrounding countryside along with a bird's eye view of the monastic site below. There's a small herd of Red Deer and you'll likely encounter wild goats along the way. The circuit is about 6 miles around as I recall and is well worth the effort if you're into pretty walks in the countryside.

You're most welcome. When we went, we ate here, just outside Glendalough, and I remember liking it- and if it's nice weather you can sit outside: https://wicklowheather.ie/

I stayed 2 nights nearly and ate at both Wicklow Heather Restaurant and Lynhams of Laragh. If you take the Old Military Road, you will pass both as you turn toward Glendalough. Either would be a fine choice, but perhaps the first is a bit more what you are looking for.

Love all these recommendations. Wrote everything down and will be checking out all it. Thanks everyone!!

Just a thought, but there are several rental car offices in the city that are convenient for getting out of town but their operating hours are pretty restrictive, ie late opening and early closing times.
The airport concessions open early - as early as 5:30 AM in some cases - and stay open until much later in the evening, which might be the better way to go if your intention is to just rent for the day. They'll have a better selection of cars too, with a better likelihood of getting an automatic versus a manual shifter which is the default rental unless you specify otherwise.
Know too that the airport rental car lot isn't physically located near the terminal but about a half mile away along Swords Rd.