I'm not really starting from scratch, I was able to pretty much start off where I left off as far as how much I could lift (which I had greatly improved from when I first started years back). I'll probably do lower body workout tomorrow. Decided to give my body a break given it's been a while.
Being a beginner isn't really about how much you are lifting (although the
weightlifting standards can be a useful guide) but how fast you are able to increase strength. If you can add even a little weight to your work sets almost every time you hit the gym, you are a beginner and can (and should!) use beginner programming. If you can only make progress every few sessions, then intermediate programming may be more appropriate. In other words, you should
want to be a beginner for as long as possible as that is the time you'll make the fastest gains.
I'm thinking of going maybe Monday, Tuesday, then Thursday, Friday instead. Is that better? I really don't want to go on weekends since it's harder, in the week at least it's just part of my daily routine, I finish work then go straight to the gym.
Yes, that schedule is better, assuming you are alternating upper and lower each day. Probably the most efficient alternative is to go 3 non-consecutive days per week (e.g. Mon, Weds, Fri) and do full body workouts each time (which is what you do in the routines I recommended above).
100 pounds is quite a lot to bench for someone my size so that is a far fetched goal for me, so that's pretty much just a passive goal not something I'm seriously aiming towards.
Assuming you are male and 150lbs, a 100lb bench press is very, very low. For example, according to the the
weightlifting standards, an
untrained 150lb male should be able to bench ~109lbs. If you've done any training at all, it should be quite a bit higher than that. I'm not saying this to be insulting, but rather to bring up the point that (a) you are most likely a beginner and (b) your current routine may be very sub-optimal. What exactly are you doing each day?
There are some machines where I can move close to 100 pounds but machines tend to be easier especially leg workouts. I forget where I was at with leg press, but it was something like 300 pounds. 3 45's on both sides and I'm guessing with the weight of the "holder" it is near 300 pounds. When I first joined I could only do 1 45.
Don't use machines. Compared with free weights, machines are less effective at building strength and the strength they build is not as "functional" (usable in the real world). Seriously, pick up a copy of
Starting Strength so you understand what weight training is really all about.