Hiya Steve,
to IIS. Plenty of free advice in here.
Your 25 mm Ep should give good views but stars will always be bright little pinpoints really. But it will let you find Globular Clusters, the faint dust clouds of Nebulae, possibly galaxies and planets and their moons. Try Jupiter at present, bright in the north and you should find 4 moons quite easily.
You will need more magnification for planet detail and good seeing (stable skies).
My main viewing EPs are GSO Superview 20mm and 15mm ( I have a 10" f5 scope). They are well priced IMHO and worth the money for my purposes. Barlows I am not keen on, they dim and can distort the view some what if you don't buy a good (expensive) one>
I'd also look at a 12mm or 9 or 10mm rather than a barlow and later if your skies are really good maybe a 6 mm.
Get Stellarium loaded onto your PC, free and one of the best astro progams around so you know what to look for. Google will find it.
And to whet your appetite for nebulae and stunning views take a look at Orions Sword and M42 the middle section of it. Probably the brightest Neb around. It will eb dim dust lanes but in good seeing to possible to discern some colour sometimes. Just above Orions three star belt, NE at present in the evening.