Mixing Amps in a HT Set-up?

I currently have a nice 2 channel system consisting of the following:

1 pair of Genesis 350SE (w/ 1500 watt bass amp)
2 - BEL 1001 Power Amps (mono operation,200x8ohms/400x4ohms)
Sonic Frontiers Line 2 SE preamp (Surr Sound Proc bypass)
Cambridge Audio D500SE cd player
P-1A/P-3A Perpetual Technolgies
Stealth Audio Magic
Ar Turntable

I have recently purchased the 38" Loewe TV set and want to incorporate my 2 channel system into a HT system. Because of the low WAF factor on the Genesis, I agreed to go with 4 of the small Linn speakers (wired and mounted on the walls) as surrounds. I am considering several SSP in the $3K to $4K range (Anthem, Krell, Aragon, Sunfire, etc.). Being a newbie to HT I have the following questions:

1. Can I use the BEL amps to power my Genesis 350 SEs as the front mains in a home theater setup?

2. Would the home theater bypass on the SF preamp allow me to go back and forth between 2 channel audio and HT without unplugging and re-plugging equipment?

3. A saleman in a local hi-fi shop told me that I probably could not use my BEL amp in a HT set-up as there would be a difference in the power ratings between the BELs and the amps I would use for the surrounds. Is he correct? Instead of purchasing a 7 channel amplifier, I was hoping to purchase a 5 channel amp and use my BELs.

Any other insights or advice as to the best way to accomplish the integration of my current 2 channel system with a future HT system would be appreciated.

Yes,Yes and he.s nuts.
On #3, as long as you calibrate the system using a sound meter, you'll be fine. Did the salesman have a "special deal" on a 7-channel amp he was recommending by any chance?
As far as using different amps, yes you can, however you will encounter a balance problem beyond simply calibrating the system with a sound meter as Kthomas has suggested. You will find that yes, that can easily be done, but the volumes of the different speakers, and especially when they are different speakers and amps, will vary with input volume. In other words, it might be perfect @ 80dB, but the fronts might be louder at higher volumes and the rears louder at lower volumes or vice versa.

Having gone through several different combinations of speakers and amps, this ultimately led me to use all the same amps, and all similar speakers to keep the balance in check at the various volumes.

...just one more thing, some people might be inclined to blow this difference off, but it IS VERY SIGNIFICANT in HT as the dynamic range can be huge......

Just my .02.
It’s all simply boils down to your priorities.
If you just want to add decent 5/7 ch. Just buy a nice receiver with 5 or 7 speakers package.
All together will cost you less than prepro you are planning to buy.
I really don’t think than you need more for your 38” TV
If you want really good HT integrated system, most modern processors in that range have very sophisticated calibrating capabilities . (BTW, I would add EAD to that list).
However, in serious HT setup it’s a good idea to have matching speakers / amplification on front 3 channel.