something that i can ride for a few hours and not regret

normal riding would be recreational, maybe a max 20-30 miles per go... not going to use it as daily transportation, I plan to do some indoor training with it during the crappy months. i dont anticipate going on any long long tours but i would like to know that i could if i get to be that serious about cycling.

current bike is a 1997 model Schwinn Frontier. Fixed fork, 21 speeds... just a basic mtn bike.

today i went to 2 bike shops, one didnt have a lot in stock but they were really really helpful, didnt seem to persuade me into anything in particular but made some good suggestions. They carry Specialized and Felt... the Felt were a little rich for me so we focused on the Specialized... they carry other bikes too but those were the 2 names they suggested for road/tour bikes...

the other place had a whole bunch of treks, among others... i saw one trek i liked but the sales chick (who didnt seem all that interested in making a sale...) told me that if i went with a base bike, i would regret it and just end up buying a more expensive bike after a year... so i might as well just spend the $ now... it didnt seem to matter to her that i might not even end up liking the whole cycling thing... the difference between the bike i liked and the one she liked was 900 bucks... she might be right but im not getting that carried away...

I looked at a couple of tricross bikes which were really cool but a cost a bit more than i want to spend... so unless i find a too good to pass up deal, that will have to be another time...

I also talked to my father in law who is an avid cyclist and he gave me some things to think about... and also told me that my brother in law has a Specialized that he is looking to get rid of and that i can probably buy it from him cheap. that's always good... so i am going to see what he has and maybe that will be what i do, at least for now until i decide if i am going to get serious about cycling or if this is just a passing phase...

so i guess now after shopping and sort of getting and idea of what's out there, are there any features/components you guys like or dislike on your own bikes that i might be cognisant of when i make a purchase?