I know what you mean.
I was raised not having much money for "extra" things. we very rarely went out or ordered takeout, we never took a real vacation (everything was day trips, mostly with relatively cheap or free admission), etc.
now that I'm married and we're not strapped for cash like that, I constantly feel guilty that some gets spent on dvd's or pizza or whatever. I feel that if we have the money to spend on those things, we have the money to put away.
of course, it's not that we're NOT saving. it's just that I'd prefer to save as much as possible, while my husband would prefer to "enjoy himself." I think part of it is that I'm just not nearly as interested in buying things as most people are (he's lucky
) - if it was up to me we wouldn't have cable, either..
what I would suggest is listing all your income and listing your mandatory expenses (rent, electric, water, car, insurance, loans, etc). then look at what you spend on food. can you cut back on takeout or snacks? or buy more store brand stuff (especially for products that you can't tell the difference, like cheeze, sugar, flour or pasta)? make sure you have enough to eat healthy but still have a bit to splurge every once in awhile.
next you should make sure you build up at least 6 months of an emergency fund - that is, in a regular savings account or money market where you can take it out whenever you need it, as opposed to an ira or cd with time restrictions.
make sure you have money to give to your church and/or charities.
whatever's left should go into an ira of some sort.
basically, live as frugally and simply as possible without driving yourself nuts. you don't want to be miserly, but it's healthy to feel the pinch a little bit and not be able to buy everything you want all the time.
as far as an actual dollar amount, that's pretty much impossible to pin down. we don't know what inflation will be like, or what health issues we might have once we retire, etc etc. I don't see why you shouldn't save as much as possible, and make sure in your will or as the beneficiary you have someone listed who can use it in case you die before you run out - which ideally would be the case - you can even list charities or the church.